Читать книгу A History of North American Birds, Land Birds. Volume 1 - Robert Ridgway - Страница 2

INTRODUCTION

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The class of Birds (Aves), as represented in the present age of the world, is composed of very many species, closely related among themselves and distinguished by numerous characters common to all. For the purposes of the present work it is hardly necessary to attempt the definition of what constitutes a bird, the veriest tyro being able to decide as to the fact in regard to any North American animal. Nevertheless, for the sake of greater completeness, we may say that, compared with other classes,1 Birds are abranchiate vertebrates, with a brain filling the cranial cavity, the cerebral portion of which is moderately well developed, the corpora striata connected by a small anterior commissure (no corpus callosum developed), prosencephalic hemispheres large, the optic lobes lateral, the cerebellum transversely multifissured; the lungs and heart not separated by a diaphragm from the abdominal viscera; aortic arch single (the right only being developed); blood, with nucleated red corpuscles, undergoing a complete circulation, being received and transmitted by the right half of the quadrilocular heart to the lungs for aeration (and thus warmed), and afterwards returned by the other half through the system (there being no communication between the arterial and venous portions); skull with a single median convex condyle, chiefly on the basi-occipital (with the sutures for the most part early obliterated); the lower jaw with its rami ossifying from several points, connected with the skull by the intervention of a quadrate bone (homologous with the malleus); pelvis with ilia prolonged in front of the acetabulum, ischia and pubes nearly parallel with each other, and the ischia usually separated: anterior and posterior members much differentiated; the former modified for flight, with the humerus nearly parallel with the axis of the body and concealed in the muscles, the radius and ulna distinct, with two persistent carpal bones, and two to four digits; the legs with the bones peculiarly combined, (1) the proximal tarsal bones coalescing with the adjoining tibia, and (2) the distal tarsal coalescing with three (second, third, and fourth) metatarsals (the first metatarsal being free), and forming the so-called tarsometatarsus; dermal appendages developed as feathers: oviparous, the eggs being fertilized within the body, excluded with an oval, calcareous shell, and hatched at a temperature of about 104° F. (generally by the incubation upon them of the mother).2

Such are some of the features common to all the existing species of birds.3 Many others might be enumerated, but only those are given which contrast with the characteristics of the mammals on the one hand and those of the reptiles on the other. The inferior vertebrates are distinguished by so many salient characters and are so widely separated from the higher that they need not be compared with the present class.

Although birds are of course readily recognizable by the observer, and are definable at once, existing under present conditions, as warm-blooded vertebrates, with the anterior members primitively adapted for flight,—they are sometimes abortive,—and covered with feathers, such characteristics do not suffice to enable us to appreciate the relations of the class. The characteristics have been given more fully in order to permit a comparison between the members of the class and those of the mammals and reptiles. The class is without exception the most homogeneous in the animal kingdom; and among the living forms less differences are observable than between the representatives of many natural orders among other classes. But still the differences between them and the other existing forms are sufficient, perhaps, to authorize the distinction of the group as a class, and such rank has always been allowed excepting by one recent naturalist.

But if we further compare the characters of the class, it becomes evident that those shared in common with the reptiles are much more numerous than those shared with the mammals. In this respect the views of naturalists have changed within recent years. Formerly the two characteristics shared with the mammals—the quadrilocular heart and warm blood—were deemed evidences of the close affinity of the two groups, and they were consequently combined as a section of the vertebrates, under the name of Warm-blooded Vertebrates. But recently the tendency has been, and very justly, to consider the birds and reptiles as members of a common group, separated on the one hand from the mammals and on the other from the batrachians; and to this combination of birds and reptiles has been given the name Sauropsida.

As already indicated, the range of variation within this class is extremely limited; and if our views respecting the taxonomic value of the subdivisions are influenced by this condition of things, we are obliged to deny to the groups of living birds the right which has generally been conceded of ranking as orders.

The greatest distinctions existing among the living members of the class are exhibited on the one hand by the Ostriches and Kiwis and the related forms, and on the other by all the remaining birds.

These contrasted groups have been regarded by Professor Huxley as of ordinal value; but the differences are so slight, in comparison with those which have received ordinal distinction in other classes, that the expediency of giving them that value is extremely doubtful; and they can be combined into one order, which may appropriately bear the name of Eurhipidura.

An objection has been urged to this depreciation of the value of the subdivisions of the class, on the ground that the peculiar adaptation for flight, which is the prominent characteristic of birds, is incapable of being combined with a wider range of form. This is, at most, an explanation of the cause of the slight range of variation, and should not therefore affect the exposition of the fact (thereby admitted) in a classification based on morphological characteristics. But it must also be borne in mind that flight is by no means incompatible with extreme modifications, not only of the organs of flight, but of other parts, as is well exemplified in the case of bats and the extinct pterodactyls.

Nor is the class of birds as now limited confined to the single order of which only we have living representatives. In fossil forms we have, if the differences assumed be confirmed, types of two distinct orders, one being represented by the genus Archæopteryx and another by the genera Ichthyornis and Apatornis of Marsh. The first has been named Saururæ by Hæckel; the second Ichthyornithides by Marsh.

Compelled thus to question the existence of any groups of ordinal value among recent birds, we proceed now to examine the grounds upon which natural subdivisions should be based. The prominent features in the classification of the class until recently have been the divisions into groups distinguished by their adaptation for different modes of life; that is, whether aerial or for progression on land, for wading or for swimming; or, again, into Land and Water Birds. Such groups have a certain value as simply artificial combinations, but we must not be considered as thereby committing ourselves to such a system as a natural one.

The time has scarcely arrived to justify any system of classification hitherto proposed, and we can only have a sure foundation after an exhaustive study of the osteology, as well as the neurology and splanchnology, of the various members. Enough, however, has already been done to convince us that the subdivision of the class into Land and Water Birds does not express the true relations of the members embraced under those heads. Enough has also been adduced to enable us to group many forms into families and somewhat more comprehensive groups, definable by osteological and other characters. Such are the Charadrimorphæ, Cecomorphæ, Alectoromorphæ, Pteroclomorphæ, Peristeromorphæ, Coracomorphæ, Cypselomorphæ, Celeomorphæ, Aëtomorphæ, and several others. But it is very doubtful whether the true clew to the affinities of the groups thus determined has been found in the relations of the vomer and contiguous bones. The families, too, have been probably, in a number of cases, especially for the passerine birds, too much circumscribed. The progress of systematic ornithology, however, has been so rapid within the last few years, that we may be allowed to hope that in a second edition of this work the means may be furnished for a strictly scientific classification and sequence of the families. (T. N. G.)

A primary division of recent birds may be made by separation of the (a) Ratitæ, or struthious birds and their allies,—in which the sternum has no keel, is developed from lateral paired centres of ossification, and in which there are numerous other structural peculiarities of high taxonomic import,—from the (b) Carinatæ, including all remaining birds of the present geologic epoch. Other primary divisions, such as that into Altrices and Præcoces of Bonaparte, or the corresponding yet somewhat modified and improved Psilopaedes and Ptilopaedes of Sundevall, are open to the serious objections that they ignore the profound distinctions between struthious and other birds, require too numerous exceptions, cannot be primarily determined by examination of adult specimens, and are based upon physiological considerations not necessarily co-ordinate with actual physical structure.

In the following scheme, without attempting to indicate positive taxonomic rank, and without committing myself finally, I present a number of higher groups into which Carinate birds may be divided, capable of approximately exact definition, and apparently of approximately equivalent taxonomic value. Points of the arrangement are freely drawn from the writings of various authors, as will be perceived by those competent to judge without special references. I am particularly indebted, however, to the late admirable and highly important work of Professor Sundevall,4 from which very many characters are directly borrowed. The arrangement, in effect, is a modification of that adopted by me in the “Key to North American Birds,” upon considerations similar to those herewith implied. The main points of difference are non-recognition of three leading groups of aerial, terrestrial, and natatorial birds,—groups without morphological basis, resting simply upon teleological modification; a general depreciation of the taxonomic value of the several groups, conformably with the considerations presented in the preceding pages of this work; abolishing of the group Grallatores; and recognition of a primary group Sphenisci.5

A. PASSERES. 6 Hallux invariably present, completely incumbent, separately movable by specialization of the flexor hallucis longus, with enlarged base and its claw larger than that of the middle digit. Neither second nor fourth toe versatile; joints of toes always 2, 3, 4, 5, from first to fourth. Wing-coverts comparatively short and few; with the exception of the least coverts upon the plica alaris, arranged in only two series, the greater of which does not reach beyond the middle of the secondary remiges.7 Rectrices twelve (with rare anomalous exceptions). Musical apparatus present in greater or less development and complexity. Palate ægithognathous. Sternum of one particular mould, single-notched. Carotid single (sinistra). Nature highly altricial and psilopædic.

a. Oscines.8 Sides of the tarsus covered in most or all of their extent with two undivided horny plates meeting behind in a sharp ridge (except in Alaudidæ; one of the plates imperfectly divided in a few other forms). Musical apparatus highly developed, consisting of several distinct pairs of syringeal muscles. Primaries nine only, or ten with the first frequently spurious, rarely over two thirds the length of the longest, never equalling the longest.

b. Clamatores.9 Sides of the tarsus covered with divided plates or scales variously arranged, its hinder edge blunt. Musical apparatus weak and imperfect, of few or incompletely distinguished syringeal muscles (as far as known). Primaries ten with rare exceptions, the first usually equalling or exceeding the rest.

B. PICARIÆ. 10 Hallux inconsiderable, weak or wanting, not always incumbent, not separately movable by distinction of a special muscle, its claw not longer than that of the middle toe unless of exceptional shape (e. g. Centropus). Second or fourth toe frequently versatile; third and fourth frequently with decreased number of joints. Wing-coverts for the most part larger and in more numerous series than in Passeres, the greater series reaching beyond the middle of the secondary quills (except in many Pici and some others). Rectrices commonly ten (eight to twelve). Primaries always ten, the first only exceptionally short (as in Pici). Musical apparatus wanting, or consisting of a muscular mass, or of not more than three pairs of syringeal muscles. Palate desmognathous or ægithognathous. Sternum of non-passerine character, its posterior border entire or doubly notched or fenestrate. Carotid single or double. Nature completely altricial, but young sometimes hatched with down11 (e. g. Caprimulgidæ).

a. Cypseli. Palate ægithognathous. Wings lengthened in their terminal portions, abbreviated basally, with the first primary not reduced. Tail of ten rectrices. Bill fissirostral or tenuirostral. Feet never zygodactyle nor syndactyle, small, weak, scarcely fitted for locomotion; hallux often elevated or lateral or reversed; front toes usually webbed at base, or with abnormal ratio of phalanges in length and number, or both. Sternum deep-keeled, usually entire or else doubly notched or perforate. Syringeal muscles not more than one pair.

b. Cuculi. Palate desmognathous. Wings not peculiar in brevity of proximal or length of distal portions, and with first primary not reduced. Tail of eight to twelve rectrices. Bill of indeterminate form, never cered; tongue not extensile. Feet variously modified by versatility or reversion of either first, second, or fourth toes, or by cohesion for a great distance of third and fourth, or by absence or rudimentary condition of first or second; often highly scansorial, rarely ambulatorial. Syringeal muscles two pairs at most.

c. Pici. Palate “exhibiting a simplification and degradation of the ægithognathous structure” (Huxley); wings bearing out this passerine affinity in the common reduction of the first primary and the restriction of the greater coverts. Tail of ten perfect rectrices and usually a supplementary pair. Rostrum hard, straight, narrow, subequal to head, with commonly extensile and vermiform but not furcate tongue. Feet highly scansorial. Fourth toe permanently reversed; basal phalanges of toes abbreviated. Sternum doubly notched. Salivary glands highly developed. Hyoidean apparatus peculiar.

C. PSITTACI. Bill enormously thick, short, high, much arched from the base, the upper mandible strongly hooked at the end, cered at base, and freely movable by complete articulation with the forehead, the under mandible with short, broad, truncate symphysis. Feet permanently zygodactyle by reversion of the fourth toe, which articulates by a double facet. Tarsi reticulate. Syrinx peculiarly constructed of three pairs of intrinsic muscles. Tongue short, thick, fleshy. Sternum entire or fenestrate. Clavicles weak, defective, or wanting. Orbit more or less completed by approach or union of postorbital process and lachrymal. Altricial; psilopædic.

D. RAPTORES. Bill usually powerful, adapted for tearing flesh, strongly decurved and hooked at the end, furnished with a cere in which the nostrils open. Feet strongly flexible, with large, sharp, much curved claws gradually narrowed from base to tip, convex on the sides, that of the second toe larger than that of the fourth toe, and the hinder not smaller than the second one. Feet never permanently zygodactyle, though fourth toe often versatile; anterior toes commonly with one basal web; hallux considerable and completely incumbent (except Cathartidæ). Legs feathered to the suffrago or beyond. Rectrices twelve (with rare exceptions); primaries sinuate or emarginate (with rare exceptions). Sternum singly or doubly notched or fenestrate. Palate desmognathous. Carotids double. Syrinx wanting or developed with only one pair of muscles. Altricial; the young being weak and helpless, yet ptilopædic, being downy at birth.

E. COLUMBÆ. Bill straight, compressed, horny at the vaulted tip, which is separated by a constriction from the soft membranous basal portion. Nostrils beneath a soft, tumid valve. Tomia of the mandibles mutually apposed. Frontal feathers sweeping in strongly convex outline across base of upper mandible. Legs feathered to the tarsus or beyond. Hallux incumbent (with few exceptions), and front toes rarely webbed at base. Tarsus with small scutella in front, or oftener reticulate, the envelope rather membranous than corneous. Head very small. Plumage without after-shafts. One pair of syringeal muscles. Sternum doubly notched, or notched and fenestrate on each side. Carotids double. Palate schizognathous. Monogamous, and highly altricial and psilopædic.

F. GALLINÆ. Bill generally short, stout, convex, with an obtuse vaulted tip, corneous except in the nasal fossa, and without constriction in its continuity. Nostrils scaled or feathered. Tomia of upper mandible overlapping. Frontal feathers forming re-entrant outline at the base of upper mandible. Legs usually feathered to the tarsus or beyond. Hallux elevated, with few exceptions (e. g. Cracidæ and Megapodidæ), smaller than the anterior toes, occasionally wanting (as in the Hemipods). Tarsus, when not feathered, generally broadly scutellate. Front toes commonly webbed at base. Claws blunt, little curved. Wings strong, short, and concavo-convex. Rectrices commonly more than twelve. Head small. Plumage usually after-shafted. Carotids double (except Turnicidæ and Megapodidæ). No intrinsic syringeal muscles. Sternum very deeply, generally doubly, notched. Palate schizognathous. Chiefly polygamous. Præcocial and ptilopædic.

G. LIMICOLÆ. Tibiæ bare of feathers for a variable (sometimes very slight) distance above the suffrago. Legs commonly lengthened, sometimes excessively so, and neck usually produced in corresponding ratio. Tarsi scutellate or reticulate. Toes never coherent at base; cleft, or united for a short distance by one or two small movable basal webs (palmate only in Recurvirostra, lobate only in Phalaropodidæ). Hallux always reduced, obviously elevated and free, or wanting; giving a foot of cursorial character. Wings, with few exceptions, lengthened, pointed, and flat; the inner primaries and outer secondaries very short, forming a strong re-entrance on the posterior border of the wing. Tail shorter than the wing, of simple form, and of few feathers, except in certain Snipes. Head globose, sloping rapidly down to the contracted base of the bill, completely feathered (except Philomachus ♂). Gape of bill short and constricted; tip usually obtuse; bill weak and flexible. Rostrum commonly lengthened, and more or less terete and slender; membranous wholly or in great part, without hard cutting edges. Nostrils narrow, placed low down, entirely surrounded with soft skin; nasal fossæ extensive. Palate schizognathous. Sternum usually doubly, sometimes singly, notched. Carotids double. Pterylosis of a particular pattern. Nature præcocial and ptilopædic. Comprising the “Plover-Snipe” group; species of medium and small size, with never extremely compressed or depressed body; more or less aquatic, living on plains and in open places, usually near water, nesting on the ground, where the young run freely at birth.

H. HERODIONES. Tibiæ naked below. Legs and neck much lengthened in corresponding ratio. Toes long, slender, never coherent at base, where cleft, or with movable basal webbing. Hallux (as compared with that of the preceding and following group) lengthened, free, and either perfectly incumbent or but little elevated, with a large claw, giving a foot of insessorial character. Wings commonly obtuse, but broad and ample, without marked re-entrance on posterior border, the intermediate remiges not being much abbreviated. Tail short and few-feathered. Head narrow, conico-elongated, gradually contracting to the large, stout base of the bill; the loral and orbital region, or the whole head, naked. Gape of the bill deeply fissured; tip usually acute; tomia hard and cutting. Bill conico-elongate, always longer than the head, stout and firm. Nostrils small, placed high up, with entirely bony and horny, or only slightly membranous, surroundings. Pterylosis nearly peculiar in the presence, almost throughout the group, of powder-down tracts, rarely found elsewhere; pterylæ very narrow. Palate desmognathous. Carotids double. Altricial. Comprising the Herons, Storks, Ibises, etc. (not Cranes). Species usually of large stature, with compressed body and very long S-bent neck; perching and nesting usually in trees, bushes, or other high places near water; young hatching weak, scarcely feathered, and reared in the nest.

I. ALECTORIDES. 12 Tibiæ naked below. Neck, legs, and feet much as in the last group, but hallux reduced and obviously elevated, with small claw, the resulting foot cursorial (natatorial and lobate in Fulica). Wings and tail commonly as in Herodiones. Head less narrowed and conic than in the last, fully feathered or with extensive baldness (not with definite nakedness of loral and orbital regions). Bill of various shape, usually lengthened and obtuse, never extensively membranous. Rictus moderate. Nostrils lower than in Herodiones. Pterylosis not peculiar. Palate schizognathous. Carotids double. Nature præcocial and ptilopædic. Comprising the Cranes and Rails and their allies; the former agreeing with the Herodiones superficially in stature, etc., but highly diverse in the schizognathous palate, præcocial nature, etc.

J. LAMELLIROSTRES. Feet palmate; tibiæ feathered (except Phœnicopterus). Legs near centre of equilibrium of the body, its axis horizontal in walking; not lengthened except in Phœnicopterus. Knee-joint rarely exserted beyond general skin of the body. Wings moderate, reaching when folded to, but not beyond, the usually short and rounded (exceptionally long and cuneate) tail. Feet tetradactyle (except sometimes in Phœnicopterus); hallux reduced, elevated and free, often independently lobate. Bill lamellate, i. e., furnished along each commissural edge with a regular series of mutually adapted laminæ or tooth-like processes, with which correspond certain laciniate processes of the fleshy tongue, which ends in a horny tip. Bill large, thick, high at base, depressed towards the end, membranous to the broad obtuse tip, which is occupied by a horny “nail” of various shape. Nostrils patent, never tubular; nasal fossæ slight. No gular pouch. Plumage dense, to resist water. Eyes very small. Head high, compressed, with lengthened, sloping frontal region. Palate desmognathous. Reproduction præcocial; young ptilopædic. Eggs numerous. Carotids double. Sternum single-notched. Comprising Flamingoes and all the Anserine birds.

K. STEGANOPODES. Feet totipalmate; hallux lengthened, nearly incumbent, semilateral, completely united with the second toe by a full web. Tibiæ feathered; position of legs with reference to axis of body variable, but generally far posterior; knee-joint not free. Wings and tail variable. Bill of very variable shape, never lamellate, wholly corneous; its tomia often serrate; external nares very small or finally abortive. A prominent naked gular pouch. Tarsi reticulate. Sternum entire or nearly so; furculum confluent with its keel. Carotids double. Palate highly desmognathous. Reproduction altricial; young psilopædic or ptilopædic. Eggs three or fewer.

L. LONGIPENNES. (To most of the characters of the group here given the genus Halodroma is a signal exception, though unquestionably belonging here.) Feet palmate. Tibiæ feathered. Legs at or near centre of equilibrium, affording horizontal position of axis of body in walking. Knee scarcely buried in common integument; tibia sometimes with a long apophysis. Hallux elevated, free, functionless; very small, rudimentary, or wanting. Rostrum of variable shape, usually compressed and straight to the hooked end, sometimes entirely straight and acute, commonly lengthened, always corneous, without serration or true lamellæ. Nostrils of various forms, tubular or simply fissured, never abortive. No gular pouch. Wings very long and pointed, surpassing the base and often the end of the large, well-formed, few-feathered tail. Carotids double. Palate schizognathous. Reproduction altricial; young ptilopædic. Eggs three or fewer. Habit highly volucral.

M. PYGOPODES. Feet palmate or lobate. Tibiæ feathered, often with a long apophysis, always buried in common integument nearly to the heel-joint, necessitating a more or less erect posture of the body on land, where progression is difficult. Hallux small, elevated or wanting; feet lobate or palmate. Bill of indeterminate shape, wholly corneous, never lamellate or serrate, nor with gular pouch. Nostrils not abortive. Wings very short, reaching scarcely or not to the base, never to the tip, of the short, sometimes rudimentary, tail. Palate schizognathous. Carotid usually double, sometimes single (in Podiceps and Mergulus). Nature altricial or præcocial; young ptilopædic. Highly natatorial.

N. SPHENISCI. With general characters of the last group, but distinguished by unique ptilosis and wing-structure, etc. Plumage without apteria, of singularly modified scale-like feathers on most parts; no developed remiges. Wings unfit for flight, insusceptible of perfect flexion or extension, very short, with peculiarly flattened bones and stable articulations. Skeleton non-pneumatic. Many bones, terete in ordinary birds, here flattened. Metatarsal bone flattened transversely, doubly fenestrate. Hallux elevated, lateral, minute, free. No free pollex. Two anconal sesamoids; patella from double centres; tibia without apophysis; a free tarsal ossicle. Sternum with long lateral apophyses. Pelvic connections unstable. Carotids double. Comprising only the Penguins. Confined to the Southern Hemisphere.

Having thus presented and defined an arrangement of the higher groups into which recent Carinate birds are susceptible of division, I next proceed to the consideration of the North American Families of birds which the authors of the present work have provisionally adopted as suitable to the end they had in view. Professor Baird urges the caution that the scheme is intended merely for the convenient determination of the North American species, aware that in many instances diagnoses or antitheses of entire pertinence in such application would fail or be negatived by consideration of the exotic forms. The arrangement of the families here adopted is essentially that presented in 1858 in Professor Baird’s “Birds of North America,” modified somewhat in accordance with more recent views of Professor Sundevall and others. But before proceeding to the analysis of the families, I will introduce an artificial clew to the preceding higher groups as adopted, so far as they are represented by North American species.

ARTIFICIAL KEY TO THE FOREGOING HIGHER GROUPS,

By means of which any North American bird may be readily referred to that group to which it is held to belong.

I. Toes 3; 2 in front, 1 behind (Pici) Picariæ.

II. Toes 3; all in front.

Toes cleft or semipalmate Limicolæ.

Toes palmate.

Nostrils tubular Longipennes.

Nostrils not tubular Pygopodes.

III. Toes 4; 2 in front, 2 behind.

Bill cered and hooked Psittaci.

Bill neither cered nor hooked. (Cuculi or Pici) Picariæ.

IV. Toes 4; 3 in front, 1 behind.

1. Toes syndactyle (Cuculi) Picariæ.

2. Toes totipalmate (all four full-webbed) Steganopodes.

3. Toes palmate.

Bill curved up Limicolæ.

Bill not curved up;

lamellate Lamellirostres.

not lamellate;

hallux lobate Pygopodes.

hallux not lobate Longipennes.

4. Toes lobate.

Tail rudimentary Pygopodes.

Tail perfect.

A horny frontal shield Alectorides.

No horny frontal shield Limicolæ.

5. Toes semipalmate;

joined by evident movable basal web (A).

6. Toes cleft to the base,

or there immovably coherent (B).

A. Hind toe elevated above the level of the rest.

Tibiæ naked below.

Nostrils perforate Alectorides.

Nostrils imperforate.

Tarsi reticulate.

Head bald Herodiones.

Head feathered Limicolæ.

Tarsi scutellate in front Limicolæ.

Tibiæ feathered below.

Nostrils perforate Raptores.

Nostrils imperforate.

Gape reaching below eye. (Cypseli) Picariæ.

Gape not reaching below eye Gallinæ.

AA. Hind toe inserted on the level of the rest.

Tibiæ naked below Herodiones.

Tibiæ feathered below.

Bill cered and hooked Raptores.

Bill not cered.

Nasal membrane soft and tumid Columbæ.

Nasal scale hard and flat Gallinæ.

B. Hind toe elevated above the level of the rest.

Gape reaching below eye (Cypseli) Picariæ.

Gape not below eye.

First primary emarginate

or about equal to 2d Limicolæ.

First primary not emarginate

and much shorter than 2d Alectorides.

BB. Hind toe inserted on the level of the rest.

Nostrils opening beneath soft swollen membrane Columbæ.

Nostrils otherwise.

Bill cered and hooked Raptores.

Bill otherwise.

Secondaries only six (Cypseli) Picariæ.

Secondaries more than six (a) Passeres.

(a) Primaries 10; the 1st

more than 23 as long as the longest. (Clamatores) Passeres.

Primaries 10; the 1st

not 23 as long as the longest. (Oscines) Passeres.

Primaries 9. (Oscines) Passeres.

Recurring now to consideration of the North American Families of the foregoing higher groups, I take up the latter in the natural order in which they have been presented, giving under head of each such group an analysis of the North American families by which it is represented, reiterating the caution that the characters are drawn up only with reference to the North American genera, and are, consequently, not necessarily or always applicable upon wider considerations. These analyses are made as nearly natural as the state of the case permits, but I seize upon any obvious external characters which may be afforded, without regard to their morphological significance or taxonomic value.

Analysis of the Families of PASSERES

A. Oscines. Musical apparatus highly developed. Back of tarsus undivided, or formed of a few scutella distinct from those lapping over the front. First primary wanting, spurious, or at most not over two thirds the length of the longest.

a. Each side of tarsus covered with a plate undivided in most or all of its length, and meeting its fellow in a sharp ridge behind.

b. Primaries only nine.

c. Bill triangular, depressed, about as wide at base as long; the gape twice as long as the culmen, reaching to about opposite the eyes; tomia straight or gently curved. No obvious rictal bristles. Tarsi not longer than the lateral toe and claw. Wings long and pointed, the first primary equal to or longer than the second. Central tail-feathers not half as long as the wing … Hirundinidæ.

cc. Bill variously conico-elongate or slender, or, if depressed, with long rictal bristles; gape not nearly twice as long as culmen; tomia straight or gently curved. Nostrils not obviously nearer culmen than tomia. Tarsus longer than lateral toe and claw.

Bill very slender, acute; culmen rather concave at base. Longest secondary acuminate, nearly or quite equal to the primaries in the closed wing. Hind claw little curved, about twice as long as the middle claw. Hind toe and claw longer than middle toe and claw … Motacillidæ.

Bill variously conico-elongate and acute; culmen not concave at base. Longest secondary not acuminate, falling far short of primaries in the closed wing. Hind claw well curved, not nearly twice as long as middle claw; hind toe and claw not longer than middle toe and claw. Gape ample; tongue slightly bifid or brushy, if at all … Sylvicolidæ.

Bill lengthened, very acute, even decurved. Wings and feet as in the last. Gape constricted; tongue generally deeply bifid or brushy … Cærebidæ.

ccc. Bill more or less truly conic, usually short, thick; commissure usually more or less evidently abruptly angulated near the base, or with lobe or tooth further forward. Nostrils obviously nearer culmen than tomia. Tarsus longer than lateral toe and claw.13

Bill stout, tumid, convex in nearly all its outlines; tomia not angulated, but with one or more lobes or nicks in advance of the base. Nostrils placed very high. Other characters much as in Sylvicolidæ. Colors chiefly red and yellow. One genus of … Tanagridæ.

Bill truly conic, much shorter than head, usually with the angulation evident; no lobe along middle of tomia, but usually a notch at end. Nostrils placed very high. Rictal bristles usually obvious … Fringillidæ.

Bill conic, but lengthened, little if any shorter than head; the angulation of the tomia evident; no notch at end. Nostrils high. No rictal bristles … Icteridæ.

bb. Primaries ten.

Otherwise with characters much as in IcteridæSturnidæ.

d. Nostrils concealed with antrorse bristly feathers (except in Psilorhinus and Gymnokitta).14

Base of bill sheathed with antrorse bristly feathers, having lateral branches to their very ends; its tip mostly notched. Basal joint of middle toe united only half-way to the lateral. Sides of tarsus occupied by a lateral groove, mostly filled in with small plates. First primary more than half as long as second. Large,—over seven inches … Corvidæ.

Base of bill with two tufts of bristly feathers, ending in simple filaments without lateral branches, its tip mostly unnotched. Basal joint of middle toe united nearly all its length with the lateral. Sides of tarsus ungrooved. First primary less than half as long as second. Small,—under seven inches … Paridæ.15

dd. Nostrils exposed.

e. Tail scansorial, with rigid acute feathers. Whole bill slender, compressed, acute, decurved, unnotched, unbristled. Outer toe much longer than inner … Certhiidæ.

ee. Tail not scansorial, graduated. First primary not less (generally more) than half as long as the second, and inner toe united to the middle by at least one half (usually more) of the length of its basal joint.

Tarsus with few obscure scutella. Rictal bristles present. Bill stout, but not toothed nor hooked. Wing excessively rounded (fifth, sixth, and seventh primaries longest), much shorter than the long graduated tail. Size small. Plumage brown, unbanded … Chamæadæ.

Tarsus distinctly scutellate. Nostrils wholly exposed, scaled. No rictal bristles, but loral feathers with bristly points. Bill slender, not notched nor hooked. Wings and tail moderately rounded; neither very much shorter than the other. Size small. Color brown, etc., the wings and tail barred or undulated … Troglodytidæ.

Tarsus distinctly scutellate. Nostrils overhung (not concealed) with bristly feathers. Rictal bristles present, strong. Bill powerful, compressed, strongly notched, toothed, and hooked. Wings and tail moderate. Large. Colors black, white, and gray … Laniidæ.

eee. Tail not scansorial. First primary less than half as long as the second,16 or about half as long, in which case the inner toe is cleft nearly to its base (f and ff).

f. Basal joint of middle toe united some distance with the inner, and for half or more of its length with the outer toe.

Basal joint of middle toe shorter than that of inner toe, and wholly adherent to both inner and outer toes. Tarsus longer than middle toe and claw. Gonys more than half the length of the lower jaw. Bill stout, high, compressed; notched and abruptly hooked at tip … Vireonidæ.

Basal joint of middle toe not shorter than that of inner toe; united to the outer for about two thirds, to the inner for about one half, its length. Tarsus not longer than the middle toe and claw. Gonys less than half the length of the under jaw. Bill triangular, much depressed at base, moderately notched, and hooked at tip17Ampelidæ.

Basal joint of middle toe shorter than that of the inner toe, united to the outer for about two thirds, to the inner for about one half, its length. Tarsus longer than middle toe and claw. Gonys more than half the length of the under jaw. Bill very weak and slender, little decurved or notched at tip. Very small,—under six inches long. (Tarsi booted in Regulus, distinctly scutellate in Polioptila.) … Sylviidæ.

ff. Basal joint of middle toe quite free from the inner, and not united with the outer more than half-way.

Nostrils linear, low. No bristles or bristly points whatever about the mouth. Wings short, rounded, concavo-convex. Tail very short, nearly concealed by its coverts. Tarsi booted … Cinclidæ.

Nostrils oval. Bristles or bristly points about the mouth. Wings very long and pointed, reaching, when folded, beyond the middle of the short, square, or emarginate tail, and one and a half times or more the length of the latter; tip formed by second, third, and fourth quills; outer secondary reaching only about two thirds way to end of longest primary; spurious quill very short. Tarsi booted … Saxicolidæ.

Nostrils oval. Bristles or bristly points about the mouth. Wings moderate, not reaching, when folded, beyond the middle of the tail, and not over one and a third times as long as the latter; tip formed by third to sixth quill; outer secondary reaching in closed wing three fourths or more the length of the longest primary. Spurious quill longer, sometimes one half the second. Tarsi scutellate in Miminæ, booted in TurdinæTurdidæ.

aa. Outside of tarsus covered with two series of scutella,—one lapping entirely around in front, the other entirely around behind, and meeting at a groove on the inside; hind edge blunt. First primary spurious or apparently wanting. Hind claw much lengthened, scarcely curved. Nostrils with antrorse bristly feathers. Bill conico-elongate … Alaudidæ.

B. Clamatores. Outside of tarsus covered with a series of plates variously arranged, lapping entirely around in front and behind, to meet at a groove on the inner side.

First primary lengthened, often longest, at least over two thirds as long as the longest. Bill broad at the base, much depressed, tapering to a fine point, which is abruptly decurved; culmen rounded or flattened; gonys flattened; commissure straight, or nearly so, to the tip. Nostrils small, circular, basal; overhung, but not concealed by bristles. Mouth capacious, with broad and deeply fissured rictus, beset with numerous long strong bristles. Feet small, weak. Tail of twelve feathers … Tyrannidæ.

Analysis of the Families of PICARIÆ

Secondaries only six.

Bill tenuirostral, longer than head, nearly cylindrical. Gape constricted. Tongue filiform, extensile, bi-tubular. Wings long in terminal portion, abbreviated proximally, acute. Plumage compact, of metallic sheen. Size smallest of all birds. (Humming-Birds.) … Trochilidæ.

Secondaries more than six.

Feet syndactyle by connation of outer and middle toes.

Outer toe much longer than the inner, united for half its length with the middle, forming a broad sole. Tibiæ naked below. Bill longer than head, straight, acute, with hard cutting edges and ample rictus. Tongue rudimentary, fixed. Wings pointed, much longer than the short square tail. Tail-feathers twelve. Plumage compact, oily. (Kingfishers.) … Alcedinidæ.

Feet zygodactyle18 by reversion of outer or fourth toe.

Not scansorial; tail of eight or ten long soft feathers. Bill with decurved tip, not fitted for hammering; rictus ample. Tongue not extensile nor vermiform nor barbed. Salivary glands and hyoidean apparatus not peculiar. No nasal tufts of feathers. Arboreal and terrestrial. (Cuckoos.) … Cuculidæ.

Highly scansorial; tail of twelve rigid acuminate feathers, whereof the outer pair are short and spurious, concealed between bases of next two pairs. Bill stout, straight, with the tip truncate or acute, not decurved,—an efficient chisel for hammering and boring wood. Tongue vermiform, extensile,19 and barbed. Salivary glands large; hyoidean apparatus peculiar. Nasal tufts usually present. Arboreal. (Woodpeckers.) … Picidæ.

Feet neither syndactyle nor zygodactyle.

Feet semipalmate, of normal ratio of phalanges. Anterior toes connected at base by movable webbing. Hind toe very small, elevated, semilateral. Middle toe produced, its large claw pectinate. Bill fissirostral, with very small, triangular, depressed horny part and immense rictus, reaching below the eyes, furnished with bristles. Rather large. Plumage soft and lax, much variegated … Caprimulgidæ.

Feet scarcely or not semipalmate, of frequently abnormal ratio of phalanges (middle or outer toe, or both, with fewer joints than usual among birds). Hallux very small, elevated, frequently lateral or versatile. Middle toe not produced nor its claw pectinate. Bill much as in the last, but rictus unbristled. Small. Plumage compact, of few simple subdued colors … Cypselidæ.

Family of PSITTACI

To characters of Psittaci add: Cere feathered, concealing the nostrils. Feet granular, rugose. Wings pointed. Tail cuneate. Plumage coarse and dry. Head feathered. Colors green, with yellow and blue … Psittacidæ.20

Analysis of Families of RAPTORES

Feet highly raptorial, with large, strong, sharp, curved, contractile claws, adapted for grasping. Hallux perfectly incumbent, lengthened (more than half as long as the fourth toe), with large claw. Front toes with slight basal webbing between outer or middle ones, or none; outer toe often reversible. Nostrils imperforate. Bill short, stout, not notably contracted in its continuity, with strongly hooked tip; tomia often once-twice toothed or lobed. Head feathered wholly or in greatest part. Lower larynx developed with one pair of muscles. Plumage with or without after-shafts. Cœca present, as a rule, if not always.

Physiognomy peculiar by reason of great lateral expansion and lengthwise shortening of the cranium, causing the eyes to be directed forward. Eyes surrounded by a disc of radiating bristly feathers, in front closely appressed to and hiding the base of the bill, elsewhere bounded by a rim of differently formed feathers. Tomia never toothed or lobed. Nostrils usually at the edge of the cere. Outer toe completely versatile, shorter than the inner toe. Basal phalanx of middle toe not longer than the second, and much shorter than the next. Legs commonly feathered or bristly to or on the toes. Plumage peculiarly soft and lax, without after-shafts; flight perfectly noiseless. Cranial walls widely separated by intervention of spongy diploë. Sternum commonly doubly notched. Chiefly nocturnal … Strigidæ.

Physiognomy not peculiar in any lateral expansion of the cranium; the eyes lateral in direction. No complete facial disc; base of bill not hidden by appressed bristles. Nostrils wholly in the cere. Outer toe rarely versatile, except Pandion, etc.; not shorter than the inner. Basal phalanx of middle toe longer than the second. Legs commonly naked and scutellate or reticulate in some portion of their length; toes always bare and scaly. Plumage compact, usually with after-shafts; flight audible. Cranial walls with little diploë. Sternum commonly single-notched or fenestrate, sometimes entire. Diurnal … Falconidæ.

Feet scarcely raptorial, with lengthened, little curved or contractile, weak, short claws. Hallux elevated, shortened, not more than half as long as the fourth toe, with small claw. Front toes all webbed at base; middle toe lengthened; outer not reversible. Basal phalanx of middle toe longer than either of the succeeding. Nostrils perforate. Bill lengthened and comparatively weak, little hooked, contracted in its continuity; tomia not toothed or lobed. Head naked of feathers in greatest part; sparsely bristly. No lower larnyx developed. No cœca. After-shafts absent … Cathartidæ.

Family of COLUMBÆ

With characters essentially as in Columbæ (exclusive of those peculiar to Diduncudidæ and Dididæ). Plumage without after-shafts; the feathers with thickened, spongy rhachis loosely inserted in the skin. Head small, completely feathered, excepting sometimes a circumorbital space. Tarsi naked or only feathered a little way above. Tail of twelve feathers, or lengthened, cuneate, and of fourteen. (Hallux not perfectly incumbent in Starnænas.) … Columbidæ.

Analysis of Families of GALLINÆ

Hind toe lengthened, insistent. Tail-feathers twelve. Sides of head and throat with naked spaces. Color greenish … Cracidæ.

Hind toe shortened, elevated. Tail-feathers usually fourteen or more. No green.

Large. Tarsi, toes, and nasal fossæ naked. Head bare of feathers, sparsely bristly, with wattles and caruncles. A pectoral tuft of bristly feathers. Tarsi usually spurred in the male. Plumage iridescent … Meleagrididæ.

Medium. Tarsi wholly or in great part, sometimes also the toes, and always the nasal fossæ, feathered. Head completely feathered, excepting a definite papillate strip over the eye. Tail-feathers sixteen or more. Sides of neck usually with lengthened feathers, or a naked distensible area, or both. No spurs. Plumage without iridescence … Tetraonidæ.

Small. Tarsi, toes, and nasal fossæ naked. Head completely feathered. No peculiar feathers or tympanum on sides of neck. No spurs. Plumage not iridescent … Perdicidæ.

Analysis of Families of LIMICOLÆ

Toes not lobate. Tarsi not notably compressed.

Legs extremely long; the tarsus equalling or exceeding the tail, and feet either four-toed and palmate (Recurvirostra), or three-toed and semipalmate (Himantopus); with the bill much longer than the head, very slender, acute, and curved upward … Recurvirostridæ.

Legs moderate, stout. Tarsus shorter than tail. Bill hard, more or less contracted at base, with short nasal fossa, gonydeal angle, and ascending gonys, the tip either compressed and truncate or depressed and acute. Feet three-toed and with basal webbing (Hæmatopus), or four-toed and cleft (Strepsilas) … Hæmatopodidæ.

Legs moderate. Tarsus shorter than tail, reticulate. Hind toe wanting (except in Squatarola, where very small, and in Aphriza). Bill short, straight,—not exceeding the head (generally shorter),—shaped like a pigeon’s, with short, broad, soft nasal fossæ separated by a constriction from the enlarged, obtuse, horny terminal part. Head large, globose, contracting suddenly to the bill. Neck short … Charadriidæ.

Legs moderate. Tarsus shorter than tail, scutellate. Hind toe present. Bill long,—equalling, or oftener exceeding, frequently several times longer than, the head; softish and membranous to the very tip, without constriction in its continuity; straight or variously curved … Scolopacidæ.

Toes lobate. Tarsi notably compressed.

General characters of Scolopacidæ. Body depressed; the under plumage thickened, duck-like. Habits natatorial … Phalaropodidæ.

Analysis of Families of HERODIONES

Hallux lengthened, perfectly incumbent, with large claw. Tarsi scutellate. Middle claw pectinate. Bill perfectly straight, tapering, acute. Loral region definitely naked, continuous with covering of the bill. Head narrow, elongate, tapering … Ardeidæ.

Hallux somewhat reduced, less perfectly incumbent. Tarsi commonly reticulate. Middle claw not pectinate. Lores, gular space and usually more of the head, naked. Bill variously curved or with expanded tip. (Genera Tantalus, Ibis, Mycteria, and Platalea.) … Tantalidæ.

Analysis of Families of ALECTORIDES

Of great stature, with extremely long neck and legs. Part or all of the head bare. Toes much shorter than the tarsi; with basal webbing, but without lobation; hallux very short, highly elevated. Bill equalling or exceeding the head, compressed, perfectly straight, contracted about the middle, with enlarged acute terminal portion; nasal fossæ wide and deep, with large perforate nostrils … Gruidæ.

Size moderate and small; neck and legs comparatively short. Head completely feathered, excepting, in the Coots and Gallinules, a broad horny frontal plate. Toes equalling or exceeding the tarsi, simple or lobate. Bill not constricted in the middle, rather shorter than the head, straight and quite stout; or much longer, regularly slender and decurved, with long nasal fossæ. Nostrils incompletely or not perforate … Rallidæ.

Analysis of Families of LAMELLIROSTRES

Of great stature, with extraordinarily lengthened neck and legs. Bill of unique shape, bent abruptly down from the middle. Tibiæ naked below. Hind toe minute or absent. Wings rounded. Red the chief color … Phœnicopteridæ.

Of moderate size; the neck short, or, when lengthened, not accompanied by co-ordinately lengthened legs, these being always shorter than the wing. Bill straight. Tibiæ feathered below. Hind toe present; well developed and functional, though short … Anatidæ.

[Pg xxviii] Analysis of Families of STEGANOPODES

Bill rather longer than head, cleft to eyes, very stout at base, tapering to the decurved, but not hooked, tip. Nostrils abortive. Gular sac moderate, naked. Wings rather long, pointed. Tail long, stiff, cuneate, twelve to fourteen feathered. Feet nearly beneath centre of equilibrium. General configuration goose-like … Sulidæ.

Bill several times longer than head, slender but strong, depressed, perfectly straight, with small distinct hooked nail at end. Nostrils very small. Gular sac enormous. Mandibular rami meeting only at tip. Wings extremely long, with upward of forty remiges. Tail short, rounded, of twenty or more feathers. Legs beneath centre of equilibrium, extremely short and stout … Pelicanidæ.

Bill about as long as head, stout, straight, scarcely tapering, strongly hooked. Nostrils abortive. Gular sac moderate, but evident; mostly naked. Wings short. Tail large, fan-shaped, scansorial, of twelve to fourteen broad stiff feathers, exposed to the base. Legs inserted far behind centre of equilibrium … Graculidæ.

Bill rather longer than head, slender, perfectly straight, tapering to an acute tip. Gular sac small. Nostrils minute. Wings and tail, and general configuration, as in the last … Plotidæ.

Bill much longer than head, straight, stout, strongly hooked. Nostrils very small. Gular sac well developed. Wings exceedingly long, strong, and pointed. Tail exceedingly long, deeply forked. Feet extraordinarily short; tarsi partly feathered … Tachypetidæ.

Bill about as long as head, straight, stout, tapering to an acute tip. Nostrils small. Gular sac rudimentary, feathered. Wings moderate, pointed. Tail short, but with two central feathers extraordinarily prolonged and filamentous. Feet small, beneath centre of equilibrium … Phæthontidæ.

Analysis of Families of LONGIPENNES

Nostrils not tubular, lateral, perforate. Bill with continuous covering, or only broken by a sort of cere, hooked or straight to the end. Hallux small and elevated, but always present … Laridæ.

Nostrils tubular, disjoined and lateral, or oftenest superior and united in one double-barrelled tube. Covering of bill in several pieces; bill always hooked. Hallux minute, rudimentary, or absent … Procellariidæ.

Analysis of Families of PYGOPODES

Feet four-toed, palmate. Hallux lobate, connected at base with base of inner toe. Tail perfect. Head closely and completely feathered. Nostrils with a depending lobe or flap. Bill straight, compressed, acute … Colymbidæ.

Feet four-toed, lobate. Hallux lobate, free. Tail rudimentary. Head with a naked loral strip and bristly or variously lengthened feathers. Nostrils simple. Bill straight or decurved at end, compressed, acute … Podicipidæ.

Feet three-toed, palmate. Hallux absent. Tail perfect. Head closely feathered or variously crested. Nostrils simple. Bill of indeterminate shape … Alcidæ.

1

We are indebted to Professor Theodore N. Gill for the present account of the characteristics of the class of Birds as distinguished from other vertebrates, pages XI-XV.

2

Dr. Coues, in his “Key to North American Birds,” gives an able and extended article on the general characteristics of birds, and on their internal and external anatomy, to which we refer our readers. A paper by Professor E. S. Morse in the “Annals of the New York Lyceum of Natural History” (X, 1869), “On the Carpus and Tarsus of Birds,” is of much scientific value.

3

Carus and Gerstaecker (Handbuch der Zoologie, 1868, 191) present the following definition of birds as a class:—

Aves. Skin covered wholly or in part with feathers. Anterior pair of limbs, converted into wings, generally used in flight; sometimes rudimentary. Occiput with a single condyle. Jaws encased in horny sheaths, which form a bill; lower jaw of several elements and articulated behind with a distinct quadrate bone attached to the skull. Heart with double auricle and double ventricle. Air-spaces connected to a greater or less extent with the lungs; the skeleton more or less pneumatic. Diaphragm incomplete. Pelvis generally open. Reproduction by eggs, fertilized within the body, and hatched externally, either by incubation or by solar heat; the shells calcareous and hard.

4

Methodi naturalis avium disponendarum tentamen. Stockholm, 1872-73.

5

This group is insusceptible of definition. The wading birds, as usually allocated, do not possess in common one single character not also to be found in other groups, nor is the collocation of their characters peculiar.

6

Corresponding closely with the Linnæan and earlier Sundevallian acceptation of the term. Equivalent to the later Oscines of Sundevall.

7

As remarked by Sundevall, exceptions to the diagnostic pertinence of these two characters of hind claw and wing-coverts taken together are scarcely found. For, in those non-passerine birds, as Raptores and some Herodiones, in which the claw is enlarged, the wing-coverts are otherwise disposed; and similarly when, as in many Pici and elsewhere, the coverts are of a passerine character, the feet are highly diverse.

8

Laminiplantares of Sundevall plus Alaudidæ.

9

Scutelliplantares of Sundevall minus Alaudidæ.

10

Nearly equivalent to the Linnæan Picæ. Equal to the late (1873) Volucres of Sundevall.

11

A polymorphic group, perfectly distinguished from Passeres by the above characters in which, for the most part, it approximates to one or another of the following lower groups, from which, severally, it is distinguished by the inapplicability of the characters noted beyond. My divisions of Picariæ correspond respectively to the Cypselomorphæ, Coccygomorphæ, and Celeomorphæ of Huxley, from whom many of the characters are borrowed.

12

Groups G., H., and I. are respectively equal to the Charadriomorphæ, Pelargomorphæ, and Geranomorphæ of Huxley.

13

In the true conirostral or fringilliform genera the under mandible has high strong tomia, bent at an angle near the base; the corresponding portion of the upper mandible is deep, so that the nostrils are nearer the culmen than the tomia. The whole bill is more or less bent in its axis from the axis of the cranial base, so that the palate curves down, or is excavated or, as it were, is broken into two planes meeting at an angle,—one plane the anterior hard imperforate roof of the mouth, the other the back palate where the internal nares are situate (Sundevall). The single North American genus of Tanagridæ (Pyranga) is here conventionally ranged on account of its high nostrils and conic bill, although it does not show angulation of the tomia. The Icteridæ, with obviously angulated tomia, shade into the Fringillidæ in shortness and thickness of bill, and into other families in its length and slenderness.

14

These two genera, Psilorhinus and Gymnokitta, of the family Corvidæ, have naked nostrils, as under dd, but otherwise show the characters of Corvidæ.

15

With the Paridæ the authors of this work include the Nuthatches as a subfamily Sittinæ, which I prefer to dissociate and place as a group of equal grade next to Certhiidæ.

16

In the genus Ampelis and part of the Vireonidæ it is so extremely short as to appear absent, and is displaced, lying concealed outside the second (apparently first) primary, like one of the primary coverts; however, it may always be detected on close examination, differing from the coverts with which it is associated in some points of size and shape, if not also of color.

17

In Ampelis there is tendency to subdivision of the lateral plates; in Myiadestes the anterior scutella are obsolete.

18

Excepting Picoides, in which the true hind toe (hallux) is wanting; the outer or fourth toe being, however, reversed as usual, and taking the place of the hind toe.

19

Excepting Sphyrapicus, in which the tongue is not more protrusible than in ordinary birds.

20

Our species falls rather in a restricted family Aridæ, as distinguished from Psittacidæ proper.

A History of North American Birds, Land Birds. Volume 1

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