Читать книгу The Common Spiders of the United States - J. H. Emerton - Страница 6

Figs. 3, 4, 5. Gnaphosa conspersa.—4, female enlarged four times. 3, the eyes seen from in front. 5, the maxillæ, labium, and ends of the mandibles from below.

Gnaphosa conspersa.—Half an inch long and rusty black in color. In alcohol the legs and cephalothorax are dark reddish brown and the abdomen gray. The whole body is covered with fine black hairs. The cephalothorax and abdomen are about the same size and a little flattened. The legs are stout and all nearly the same length. The upper row of eyes is nearly straight and the lateral eyes much farther from the middle pair than these are from each other (fig. 3). The middle eyes are oval and oblique, diverging toward the front. The maxillæ are large, and rounded on the outer corners. The mandibles are large and strong, with a wide, flat, serrated tooth (fig. 5) under the claw. The cocoon is white and flat, with a diameter as great as the length of the spider. The female, as far as I have observed, makes no nest, but partly lines with silk a shallow hole, in which she nurses her cocoon. It lives under stones and leaves as far north as the White Mountains and west to the Rocky Mountains in British Columbia, and on the Pacific coast in Oregon. A smaller and similar species, Gnaphosa brumalis, lives on the top of Mount Washington and as far north as Labrador.

Figs. 6, 7, 8. Pythonissa imbecilla.—7, female enlarged four times. 6, the eyes seen from in front. 8, the maxillæ, labium, and ends of mandibles from below.

Pythonissa imbecilla.—About quarter of an inch long, bright orange brown on the cephalothorax and legs and blue black on the abdomen, with a few white hairs around the muscular spots. The legs are covered with fine long hairs a little darker in color than the skin. The cephalothorax is wide behind and more narrowed in front than in Gnaphosa. The eyes (fig. 6) are close together, and the lateral eyes of both rows are larger than the middle pairs and a little farther back on the head. The maxillæ (fig. 8) are short and wide, and bent toward each other so that they nearly meet in front of the labium. The front edges are nearly straight and the outer corners only slightly rounded. The sternum is wide and almost circular. The tarsus of the female palpi tapers from the base to the tip.

Figs. 9, 10, 11. Pœcilochroa variegata.—11, female enlarged four times. 9, eyes from in front. 10, maxillæ, labium, and ends of mandibles from below.

Pœcilochroa variegata.—This is one of the most brightly colored of the family. The cephalothorax is bright orange, a little darker toward the eyes. The abdomen is black, with three transverse white stripes and a T-shaped white mark between the first and second stripes. On the front of the abdomen the white stripes are sometimes tinged with orange. The femora of the first and second legs are black. The distal end of the femur and both ends of the tibia of the fourth legs are black. Other parts of the legs are orange-colored. The female is quarter of an inch long. The cephalothorax is narrower than in Prosthesima atra and Gnaphosa conspersa, and the sternum longer and narrower. The maxillæ (fig. 10) are long and widened at the outer corners. The two rows of eyes (fig. 9) are almost straight, the upper one longer than the lower.

Fig. 12. Fig. 13. Pœcilochroa bilineata.—Upper and under views of female without the legs, enlarged four times.

Pœcilochroa bilineata.—A little smaller than P. variegata, but with the abdomen longer. Cephalothorax and abdomen both white at the sides and in the middle, with two black stripes from the eyes nearly to the spinnerets. The abdomen is covered with long hairs, black in the stripes and silvery white in the light portions. The legs are gray, with white hairs. The under side is light gray, with two black stripes at the sides of the abdomen that do not quite reach the spinnerets. The spinnerets are unusually long. The eyes are arranged as in variegata, the middle eyes being even more distinctly farther apart than they are from the lateral eyes.

Figs. 14, 15, 16. Prosthesima atra.—16, female enlarged four times. 14, eyes seen from in front. 15, maxillæ, labium, and ends of mandibles from below.

Prosthesima atra.—Black, and less than a third of an inch long. It may be mistaken for a small Gnaphosa conspersa, but, besides the small size, the abdomen is usually longer in proportion and the head is narrower than in Gnaphosa. The color is usually a deeper black and less likely to be gray in the young and rusty in the old, but the feet and under side of the abdomen are sometimes yellowish in the young. The eyes (fig. 14) are closer together and the two rows more nearly of the same length. In alcohol the cephalothorax and legs are blacker than in Gnaphosa and less brown. The maxillæ (fig. 15) are a little longer and less rounded at the outer corners than in Gnaphosa or Pythonissa. The mandibles (fig. 15) are without the large teeth under the claw that Gnaphosa and Pythonissa have, and they are turned forward more than in those genera. It lives on the ground and under stones. The cocoon is white or pink, attached by the under surface, with the upper side convex and thickened in the middle, sometimes with a little dirt attached to it.

Fig. 17. Fig. 18. Prosthesima ecclesiastica.—Upper and under views of female enlarged four times.

Prosthesima ecclesiastica.—Black, with white markings along the middle of the back. One-third of an inch long, a little larger than P. atra and smaller than Gnaphosa conspersa. The cephalothorax is proportionally longer and narrower and the sternum narrower and less round than in P. atra (fig. 18). The cephalothorax is dull black at the sides, with a whitish stripe in the middle. The legs are also dull black and, like the cephalothorax, turn brown in alcohol. The abdomen is black, with a bright white stripe in the middle that extends from the front end about two-thirds its length; and at the hinder end, just over the spinnerets, is another white mark (fig. 17). The under side of the abdomen is dark at the sides and light in the middle. The eyes and maxillæ are as in P. atra, the maxillæ a little less rounded at the ends.

Fig. 19. Drassus saccatus.—Female enlarged three times. For eyes and mouth parts see figs. 1 and 2 in Introduction.

Drassus saccatus.—Four-fifths of an inch long, and pale, without markings. The head is shorter and wider than in Gnaphosa conspersa and Prosthesima atra, and the eyes cover a larger part of the head. Both rows of eyes (figs. 2, 19) are curved, with the middle highest. The middle upper pair are oval and turned apart toward the front. The lateral eyes are twice their diameter from the middle pair. The maxillæ (fig. 1) are widened at the ends on both sides. The labium is as wide as it is long, narrowed toward the end but truncated at the tip. The color is light gray, with short fine hairs all over the body. The front of the head, the feet, and the mandibles and maxillæ are darker and browner. The abdomen is marked only with the usual four muscular spots and sometimes a few transverse dark markings toward the hinder end. The legs are long and tapering in both sexes. The male is smaller and more slender than the female, and the male palpi are long, with the end very little enlarged. They live under stones, and make a large transparent bag of silk in which the female makes her cocoon of eggs, and stays with it until the young come out. Early in the summer a male and female often live together in the nest, even before the female is mature.

Figs. 20, 21, 22. Geotrecha crocata.—22, female enlarged four times. 20, eyes seen from in front. 21, maxillæ, labium, and ends of mandibles from below.

Geotrecha crocata.—Black, with the ends of the legs light yellow and a bright red spot on the end of the abdomen. It is about a third of an inch long. The legs are slender and the body is not at all flattened. The cephalothorax is two-thirds as wide as long, oval behind and narrowed in front of the legs, where the sides of the head are nearly parallel. The abdomen is oval and nearly twice as long as wide. The spinnerets are so far under the body that they show but little from above. At the front end of the abdomen is a spot larger below than above, where the skin is thicker and harder and browner in color than the rest. The cephalothorax is dark brown or black, as are also the femora of all the legs and of the palpi. The ends of the third and fourth legs are a lighter brown and the ends of the first and second legs and palpi light yellow. The abdomen is deep black except a bright red spot at the hinder end, which varies in size, is sometimes broken into several spots, or is sometimes wanting altogether. The eyes (fig. 20) are near together, the upper row curved down at the ends. The maxillæ are straight, with the sides nearly parallel, and the labium is shorter than wide. The males are usually smaller than the females and have the red spot larger. These spiders live among stones in dry open places. They are easily alarmed and move very rapidly. The flat, parchment-like cocoons found on stones are probably made by this species.

Fig. 23. Fig. 24. Geotrecha bivittata.—Upper and under views of female enlarged four times.

Geotrecha bivittata.—The same size as G. crocata but much lighter colored, and with two white stripes across the abdomen (fig. 23). The cephalothorax is a little narrower behind than it is in crocata. Its color varies from orange to dark brown. The femora of all the legs are striped lengthwise with brown and yellow. The hind legs are brown, with a little yellow on the upper side of the patella and tibia. The other legs are yellow, sometimes with brown stripes on the under side. The white marks on the abdomen extend underneath halfway to the middle line. The sternum and under side are light brown. It lives under leaves at all seasons.

Figs. 25, 26, 27, 28. Micaria longipes.—28, Male enlarged four times. 25, eyes seen from in front. 26, maxillæ, labium, and ends of mandibles from below. 27, Southern variety, Micaria aurata. Colored orange, with black and white markings.

Micaria longipes or aurata.—A quarter of an inch long or less, and resembling an ant both in size and color (fig. 28). The cephalothorax is twice as long as wide, and only a little widened in the middle. It is highest in the middle, curving downward at both ends. The front row of eyes (fig. 25) is nearly straight and the upper row curved, with the middle eyes highest and the eyes all farther apart than in the lower row. The abdomen is one-half longer than the cephalothorax and about as wide, blunt at both ends and drawn in a little at the sides and above at a point a third of its length from the front. The legs are long and slender, the fourth pair longest. The colors are light yellow brown, with gray hairs and scales which on the abdomen have green and red metallic reflections. The legs are darker from before backward, the front pair all light yellow except the femur, and the third and fourth pairs with longitudinal brown stripes that nearly cover the tarsal joints. The abdomen has a pair of transverse white stripes near the constricted part and another pair less distinct at the front end. The under side is as dark as the upper. The white markings extend underneath halfway to the middle line. The maxillæ are nearly straight on the outer edge and a little widened toward each other at the ends. The labium is narrowed at the end and a little longer than wide (fig. 26).

There is an orange-colored Micaria from Long Island, N.Y., and farther south (probably what is described by Hentz under the name Herpyllus auratus), that seems to belong to this species (fig. 27). Its size and markings are the same, and the epigynum is like that of longipes. The cephalothorax, abdomen, and femora of all the legs are bright orange color, with brilliant yellow and green reflections. The spinnerets are black, and there are five or six transverse black marks on the hinder half of the abdomen and some irregular black spots around the white bands.

Figs. 29, 30, 31, 32. Phrurolithus alarius.—31, female in a natural position, with legs drawn up over the back, enlarged eight times. 29, one of the front legs to show spines. 30, eyes from in front. 32, maxillæ, labium, and ends of mandibles.

Phrurolithus alarius.—A small and very active spider marked with gray and white and having on the abdomen iridescent green scales (fig. 31). The cephalothorax is nearly as wide behind as it is long. The head is about half as wide as the thorax. The eyes (fig. 30) are large for so small a spider, and cover more than half the width of the head. The middle eyes of the upper row are oval and turned obliquely, diverging toward the front. The labium is short and the maxillæ straight, as in Agrœca and Anyphæna, but wider at the base (fig. 32). The legs are long and slender, except the tibia and metatarsus of the first and second pairs, which are twice as thick as the same joints of the other legs and have on the under side two rows of strong spines (fig. 29). The cephalothorax is light yellowish, with a black line on the edge each side, and two light gray stripes. The abdomen is gray, with transverse white markings that vary greatly in size and shape in different individuals. The abdomen is covered with scales that change from grayish green to pink with the motions of the spider. The legs are pale, except the patella and tibia of the first pair, which are black or dark gray, with the tip of the tibia white. The tibia and patella of the second pair are marked with lighter gray in the same way. It lives among stones in open ground, and runs short distances with great swiftness. When still it lies close to a stone, with the tibiæ drawn up over the back.

Figs. 33, 34, 35, 36. Agrœca pratensis.—33, eyes from in front. 34, maxillæ, labium, and ends of mandibles. 35, back of female enlarged four times. 36, under side of female as far back as the epigynum.

Agrœca pratensis.—A little light-colored spider, resembling the next species, Anyphæna incerta. It is about a fifth of an inch long. The cephalothorax is wide behind and low in front and highest near the dorsal groove. The head is contracted in front of the legs more than it is in incerta. The front row of eyes is nearly straight, the middle pair only a little the higher (fig. 33). The upper row is longer and more curved, with all the eyes about the same distance apart, the middle pair not so much separated as in incerta. The abdomen is widest behind, but not as wide as in incerta. The spinnerets are two-jointed, as in Anyphæna. The legs are long, the fourth pair longest, and are a little thicker than those of incerta. The coxæ of the hind legs almost touch, and the sternum is short and nearly round (fig. 36). The labium is short and the maxillæ straight, as in Anyphæna. The cephalothorax, legs, and mouth parts are light brownish yellow. The cephalothorax has a fine dark line on each side and two broken longitudinal stripes made up of gray marks radiating from the dorsal groove. The abdomen has two rows of gray oblique markings on a light ground. The general appearance is like a small Lycosa. It lives among leaves and short grass. There is little difference between male and female.

Figs. 37, 38, 39, 40, 41. Anyphæna incerta.—37, palpus of male. 38, under side of female as far forward as end of sternum. 39, eyes from in front. 40, female enlarged four times. 41, maxillæ, labium, and ends of mandibles.

Anyphæna incerta.—About a fifth of an inch long, light yellow, with gray markings. The cephalothorax is three-quarters as wide as long, rounded at the sides and highest in the middle. The front of the head is very low, so that the eyes nearly touch the mandibles. The front row of eyes is nearly straight. The upper row is longer and more curved, with the middle eyes highest and farthest apart (fig. 39). The abdomen is large in the female, widest behind the middle, and a little pointed behind. The labium is not longer than wide, and the maxillæ are straight, with the sides parallel. The sternum is oval, not so short and wide as in pratensis. The opening of the air-tubes is halfway between the epigynum and spinnerets (fig. 38), instead of just in front of the spinnerets, as it is in most spiders. The spinnerets are two-jointed. The legs are slender and tapering, the fourth longest in females and the first in males. The cephalothorax has two longitudinal broken gray bands. The abdomen has a double row of spots in the middle and oblique rows of smaller spots each side. The oblique lines of spots extend under the abdomen halfway to the middle.

Figs. 42, 43. Anyphæna calcarata.—42, under side of cephalothorax of female. 43, palpus of male.

Anyphæna calcarata.—The same size and color as A. incerta, with longer legs. The markings are the same in both species. The plainest difference between the females is in the epigynum, the hard and dark parts of which are larger and longer in incerta. Another slight difference is in the shape of the sternum, which in calcarata extends farther between the hind legs (fig. 42). In incerta it is more pointed at the hinder end and shorter (fig. 38). The difference between the length of the legs in the two species, which is slight in the females, is greater in the males, the legs of calcarata being the longer. The palpi of the males differ considerably. In incerta (fig.37) the tibia of the palpus has a large process on the outer side close to the tarsus and extending along its edge a third of its length. In calcarata (fig. 43) the corresponding process is small and does not lap over the tarsus. The coxæ of the third and fourth legs of the male calcarata have little processes on the under side (fig. 42), one on the fourth and two on the third. These do not occur in incerta. It lives on plants like saltabunda (p. 14).

Figs. 44, 45. Anyphæna rubra.—44, female without the legs, enlarged four times. 45, under side of abdomen, showing position of air-tubes.

Anyphæna rubra.—Larger than the other species, with the legs shorter. The female is about a third of an inch long, with the abdomen longer and narrower than in incerta or saltabunda. The opening of the air-tubes (fig. 45) is farther forward than usual, twice as far from the spinnerets as from the epigynum. The legs are comparatively short, the longest, the fourth, being about as long as the body. The maxillæ are a little widened at the end. The sternum is widest at the second legs and narrows to a point behind. The head is a little wider than usual, and the whole appearance more like Clubiona than the other species. The color is the usual pale yellow, a little brownish on the head and legs, and with two longitudinal stripes on the cephalothorax. The abdomen is nearly white, with two stripes made up of gray spots, and scattered spots at the sides. The spots turn red in alcohol.

Figs. 46, 47. Anyphæna saltabunda.—46, female enlarged six times. 47, palpus of male.

Anyphæna saltabunda.—A pale short spider, with long and slender legs (fig. 46). The body is an eighth to a sixth of an inch long. The abdomen is oval, two-thirds as wide as long, and nearly as high as it is wide. The cephalothorax is three-fourths as wide as long, widest across the dorsal groove and narrowing gradually to half as wide in front. The eyes of the upper row are twice as large as those of the front row. The first legs are longest in both sexes, measuring in the female over twice the length of the body and in the males three times. The spines are very long on the legs and palpi but only a little darker in color. The general color is pale yellow or white, with two broken gray stripes on the cephalothorax and two middle and several lateral rows of light gray spots on the abdomen. The spinnerets are slender and two-jointed. The opening of the air-tubes is halfway between the spinnerets and the epigynum. The palpi of the male (fig. 47) are long and slender, and the tibia is slightly curved and has a large thin process on the outer side.