Читать книгу The Pleistocene of North America and its vertebrated animals - Oliver Perry Hay - Страница 48

Table of Contents

(Maps 3, 4.)

1. Archer, Alachua County.—Leidy mentioned (Proc. Acad. Nat. Sci. Phila., 1886, pp. 11, 12) the fact that an astragalus of Megatherium had been found at Archer. Several other species of vertebrates have been found there, among them Teleoceras fossiger, Gomphotherium floridanum, Hipparion plicatile, three species of Procamelus, and a species of Tapirus. The deposits are assigned to the Pliocene, but it is doubtful whether the megatherium and the tapir belonged among the others. The geology of the locality is discussed on page 375. The megatherium, as an undetermined species, is included in the list of fossils which is recorded by Leidy in Bulletin 84 of the United States Geological Survey, page 129. It may be referred provisionally to Leidy’s Megatherium mirabile.

2. Almero Farm, St. John County.—In the collection of Mr. Fred Allen, at St. Augustine, the writer has seen a right tibia of a mylodon found in the Inland Waterway Canal about 28 miles south of St. Augustine. The bone is complete, except that a sliver has been split off the upper half of the outer border. The total length of the bone is 290 mm.; the greatest width of the upper end 208 mm.; width at middle of length 105 mm.; width of surface for astragalus 130 mm. This appears to be a relatively stouter bone than the larger one described by Harlan (Amer. Jour. Sci., vol. XLIV, 1842, p. 77). It is also larger and relatively stouter than a tibia found at Labelle, Lee County, described on page 40. It is referred to Mylodon harlani.

11. Williston, Levy County.—In the U. S. National Museum there are some foot-bones of a large ground-sloth, which are labeled as having been collected in 1887 by the U. S. Geological Survey, in the county named. The collector was probably J. B. Hatcher. The astragalus had evidently been studied by Leidy. This bone was described by the writer in 1919 (Proc. U. S. Nat. Mus., vol. LVI, p. 104, plate XXVII) as Thinobadistes segnis. Later, other parts of the foot were found in the museum and described (Proc. U. S. Nat. Mus., vol. LIX, p. 638, plate CXIX, figs. 6–11).

3. Ocala, Marion County.—In 1888, in a fissure in a limestone quarry, probably Phillip’s quarry, near Ocala, Mr. Joseph Willcox discovered some vertebrate remains which were later described by Leidy (Trans. Wagner Free Inst., vol. II, pp. 13–17, plate III, figs. 1, 5, 6 to 9). The species as determined by Leidy were Elephas columbi, Equus fraternus, Auchenia minima, and Machairodus floridanus. They were regarded as belonging to the Quaternary, but in Dall’s paper of 1892 (Bull. 84, U. S. Geol. Surv., p. 129) they are referred to the age of the Alachua clays; that is, to the Pliocene. Sellards, in 1916 (8th Ann. Rep. Florida Geol. Surv., p. 103), regards the fossils as belonging to the Pleistocene, and he adds representatives of 4 genera to the list. These are undetermined species of Bison, Odocoileus, Dasypus, and Sylvilagus. The genus Dasypus is the one to which attention is especially called at this time. A list of the vertebrate animals found at this place is presented on page 378.

4. Dunnellon, Marion County.—In Sellards’s report just referred to, he prints a list of the Pleistocene vertebrates found in Withlacoochee River. Among these is the xenarthrid animal Chlamytherium septentrionale. What parts were secured and exactly at what place the writer does not know.

In the collection of the Florida Geological Survey is a foot-bone, No. 1307, which appears to be the second right metacarpal of Megalonyx. It is smaller than the one figured by Leidy. The extreme length is 60 mm., the greatest diameter of the proximal end 27 mm., that of the distal end 36 mm. It was found in the mine of the Dunnellon Phosphate Company. For a list of the associated species the reader is referred to page 376.

5. Hillsboro River, Hillsboro County.—In 1915 (Amer. Jour. Sci., vol. XL, p. 139), Sellards stated that the Jarman collection at Vanderbilt University, at Nashville, contains several dermal plates of Chlamytherium septentrionale, found in Hillsboro River.

6. Sarasota Bay, Sarasota County.—In 1915, Sellards (op. cit., p. 143) reported that the collection of Wagner Free Institute at Philadelphia contains one dermal plate of Chlamytherium septentrionale found by Joseph Willcox at White Beach, on Sarasota Bay.

The American Museum of Natural History, New York, possesses a dermal plate of a xenarthrid, collected by Barnum Brown 8 miles southeast of Sarasota. This probably belonged to the animal mentioned above.

7. Zolfo, Hardee County.—Dr. W. D. Matthew has informed the writer that there are in the American Museum of Natural History some bones of a very large individual of Megatherium, reported as having been found near Zolfo. An astragalus, the proximal part of a humerus, the distal part of a radius, and the proximal part of a femur were mentioned. These bones may be referred provisionally to Megatherium mirabile Leidy.

8. Vero, St. Lucie County.—At this place there have been found remains representing 4 genera of xenarthrids, as follows: Megalonyx, Mylodon, Chlamytherium, and Dasypus.

Megalonyx jeffersonii is represented by a part of a lower jaw, a right upper canine tooth, a molar tooth, a part of a hyoid bone, an axis, an astragalus, a median phalanx, and a claw (Sellards, 8th Ann. Rep. Florida Geol. Surv., p. 148, plate XXV, fig. 2; plate XXX, fig. 6). These were all found in the stratum denominated No. 2 in the report just cited.

Mylodon harlani? is known from a single claw, but from which stratum it was derived is not known.

Chlamytherium is represented by a part of the right side of the lower jaw, a part of the left side, a foot-bone, and numerous dermal plates (Sellards, op. cit., p. 148, plate XXVIII, figs. 4 to 6; plate XXX, fig. 7). Most of these remains have been taken from stratum No. 2, but some finely preserved dermal plates have been collected from No. 3.

Dasypus remains, consisting of dermal scutes, have been found in both No. 2 and No. 3.

In the collection of the Florida Geological Survey (No. 1795) is a bone, apparently the right parietal of an undetermined xenarthrid. It was found in the canal of the Indian River Farms Company, east of the railway and near Indian River. The length of the bone at the midline is 70 mm. and here the thickness is 22 mm. There appears to have been no median crest and only a feebly indicated occipital crest. There is no rough surface for the temporal muscles, as in Nothrotherium, and the bone is thicker than in that genus.

For complete lists of the fossil vertebrates found at Vero, see page 382.

9. Arcadia, De Soto County.—The Xenarthra are represented in the Pleistocene deposits about Arcadia by the genera Megalonyx, Glyptodon, and Chlamytherium. If these were not found at Arcadia they were collected along Peace Creek, not far from the town. A list of the species found in the vicinity of Arcadia is given on page 380.

Leidy (Trans. Wagner Free Inst., vol. II, p. 27) stated that a first phalanx of Megalonyx jeffersonii was among the fossils collected along Peace Creek. It was probably found on the sand-bar at Arcadia. Among the fossil vertebrates described by Leidy, the paper just cited included some dermal plates which he referred to the genus Glyptodon. Two of these plates were figured (op. cit., plate IV, fig. 9; plate VI, fig. 1) as those of G. petaliferus, a species based on half of a dermal scute described by Cope from southwestern Texas. The dermal scute shown on Leidy’s plate IV appears to be indistinguishable from similar plates which have been referred by the present writer to Cope’s G. petaliferus (Proc. U. S. Nat. Mus., vol. LI, 1916, p. 107, plates III to V). The scute represented by Leidy on his plate VI appears to be far less extensively pitted than any of those of the specimen just referred to. On Leidy’s plate V are two views of a scute which he thought might have belonged on the tail of a glyptodon. It will be observed that this scute has a beak distinctly set off from the body of the scute. Among the few caudal scutes of the specimen which the writer described none presents such a beak, but such may have existed. It seems probable, however, that there was a single species of Glyptodon found on Peace Creek and that it was different from G. petaliferus. Leidy thought that these caudal scutes resembled those on the tail of the South American G. asper; but Burmeister’s figures do not indicate exactly such keeled scutes. It is most probable that the Florida species requires a new name. It is to be called Glyptodon rivipacis Hay.

Leidy referred another dermal scute to some glyptodont animal (op. cit., plate VI, figs. 2, 3), but its nature is doubtful; it may even belong to one of the large species of Testudo. A conical bone (plate III, figs. 10, 11) belonged pretty certainly to Testudo.

In the paper cited Leidy described and figured (p. 24, plate III, figs. 3 to 6) plates of an armadillo-like animal to which he gave the name Glyptodon septentrionalis. It is now known as Chlamytherium septentrionale. Leidy had over 30 of these dermal scutes which had been found at Arcadia. They are now in the Wagner Free Institute at Philadelphia.

Sellards (Amer. Jour. Sci., vol. XL, 1915, p. 143) states that there are 3 dermal plates of this animal in the U. S. National Museum. In 1915 (Florida Geol. Surv., vol. VII, pp. 77, 78, plate on p. 114) he described a lower jaw, a tooth, and 2 dermal plates of the same animal.

10. Labelle, Lee County.—In the Florida Geological Survey is a right tibia of a mylodon, found on the bank of Caloosahatchee River, near Labelle, presented by Capt. F. H. Hendry. The total length is 266 mm.; on the inner border 236 mm. The width across the articulatory surface for the femur is 164 mm. The width at the middle of the length is 84 mm.; fore-and-aft diameter at the same place 38 mm. The side-to-side diameter of the surface for the astragalus is 57 mm. The bone is referred to Mylodon harlani.

11. See page 37.