THE AGALENIDAE

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Fig. 221. Web of Agalena nÆvia in long grass, seen from above. One-third the real size. Fig. 221. Web of Agalena nÆvia in long grass, seen from above. One-third the real size.

The larger AgalenidÆ are the makers of the flat wide cobwebs that are so common on the grass and in the corners of barns and cellars. They resemble some of the DrassidÆ, especially Agroeca and AnyphÆna (pp. 1-14). The head is large and marked off by shallow grooves from the thorax, and is often contracted behind the eyes, so that it is narrower there than in the front. The mandibles are large and, in the females, much swelled at the base in front. The arrangement of the eyes differs little from that in the DrassidÆ. The upper spinnerets are longer than the others and have the terminal joint narrowed toward the end, with the spinning tubes on the inner side. The feet have three claws, like the LycosidÆ, and do not have the brush of hairs common in the DrassidÆ. The males and females differ little in size, but the males have longer legs and smaller abdomen and large and complicated palpi.

Fig. 222. Web of Agalena nÆvia in short grass on the side of a hill, seen from the side. The spider stands in its usual place at the mouth of its tube. Half the real size. Fig. 222. Web of Agalena nÆvia in short grass on the side of a hill, seen from the side. The spider stands in its usual place at the mouth of its tube. Half the real size.
Figs. 223, 224. Agalena nÆvia.—223, female enlarged twice. 224, front of head. Figs. 223, 224. Agalena nÆvia.—223, female enlarged twice. 224, front of head. Fig. 225. End of palpus of male Agalena nÆvia.

Agalena nÆvia.—This spider is known everywhere by its web, which it makes on grass, among stones and weeds, and in houses (figs.221, 222). It varies greatly in size and color. Large females may be three-quarters of an inch long, with legs measuring an inch and a quarter, while others may be full grown at half that size. In color some are pale yellow with gray markings, and others reddish brown with the markings almost black. Whatever the color, they are thickly covered with fine gray hairs. The cephalothorax has two longitudinal gray stripes and a black line along the edge on each side (fig. 223). The head is high and a little darker in front. Both rows of eyes are strongly curved, with the middle eyes highest, so that the middle eyes of the lower row and the lateral of the upper row form a nearly straight line (fig.224). The mandibles are stout, not much swelled in front, and covered with hair. The abdomen is gray or black at the sides and lighter brown in the middle, with two rows of white or light-colored spots. The upper spinnerets are more than twice as long as the others, and the terminal joint much longer than the basal. The legs are large and long, the fourth pair almost twice as long as the body. The legs are marked with dark rings at the ends of the joints and lighter rings in the middle of femur and tibia. On the under side the coxÆ are light colored and the sternum dark, and there is a broad dark middle band on the abdomen from the hinder legs to the spinnerets. The males are as large as the females, with longer legs and smaller abdomen. The male palpi have a very large black tube coiled one and a half turns under the tarsus (fig. 225). The web (fig. 222) is flat and shaped according to the surrounding objects to which it is fastened, with a tube at one side in which the spider hides. The eggs are laid in August and September in a flat cocoon, attached by one side in some sheltered place and covered with silk, often mixed with dirt. Most of the adult spiders die before winter, and females are often found dead on or near their cocoons. The young hatch in the winter and leave the cocoon early in the spring, and soon begin to build their webs among the short grass. The webs become more distinct when covered with dew, but, though too transparent to be seen at other times, they remain in the same places throughout the summer and are repaired and enlarged as the spider grows. If, however, the web should be destroyed, the spider is able in one day to make a new one as large as the old, but thin and transparent. The web contains many long threads crossing it from one side to the other and nearly parallel, and these are crossed in all directions by finer threads (fig. 226). The long threads are spun from the lower spinnerets, the upper pair being held up over the back, out of the way. The fine threads are spun from the upper spinnerets, which are swung from side to side as the spider moves along. There is nothing adhesive about the web. It serves merely as a clearing where insects may alight to rest and the spider may have a good chance to run after them. Where the web is made under plants or rocks a great number of threads are carried upward from it, which may help in stopping insects (fig. 227), as they do in the webs of Linyphia. (See p. 135.)

Figs. 228, 229. Tegenaria derhamii.—228, female enlarged four times. 229, front of head. Figs. 228, 229. Tegenaria derhamii.—228, female enlarged four times. 229, front of head.

Tegenaria derhamii.—This is a common species in barns and cellars, and has probably been imported from Europe, where it is even more common. The head is high and wide, as in T. medicinalis. The mandibles are less swelled in front and the eyes are closer together than in that species, and cover more than half the width of the head (fig. 229). The cephalothorax is shorter and wider across the hinder half and the abdomen shorter than in medicinalis, and the legs are longer and more hairy. The colors are lighter and the hairs of the whole body longer. The female is two-fifths of an inch long. The cephalothorax is pale, with two gray stripes. The abdomen is marked with a series of gray spots, formed of a middle row more or less connected with two side rows; the front of the abdomen often pale, with the markings faint (fig. 228). The legs are long, the first and fourth pairs nearly twice the length of the body. They are marked with faint gray rings at the ends and two in the middle of each joint. The palpi are long and slender in both sexes, and those of the male have the patella and tibia of about the same length and each nearly twice as long as wide. There are no processes on the patella, but two small teeth on the tibia near its end. The tarsus is small and narrow, not as long as the patella and tibia.

Fig. 230. Web of Tegenaria derhamii in corner of cellar. Fig. 230. Web of Tegenaria derhamii in corner of cellar.
Fig. 231. Web of Tegenaria derhamii with spider in mouth of tube. Old cocoons hanging at the left. Fig. 231. Web of Tegenaria derhamii with spider in mouth of tube. Old cocoons hanging at the left.
Fig. 232. Web of Tegenaria derhamii curving downward on each side. Fig. 232. Web of Tegenaria derhamii curving downward on each side.

The webs are made in all parts of cellars and unswept buildings, sometimes forming a shelf in the corner, not as large or as flat as those of A. nÆvia, but with a similar tube on the most sheltered side (fig. 230). The webs more often spread under beams and floors fastened up by threads at the sides and edges, and, as they gather dust, hang down by its weight and become[Pg 98]
[Pg 99]
torn and tangled. Old webs are repaired and extended until they become as thick as cloth with silk and dirt. The tube is generally smaller and less funnel shaped where it enters the web than that of Agalena. The web is not as flat as that of Agalena, curving usually down from the tube and up in front of it, often turning up abruptly at the edge. Sometimes it is fastened up in the middle of the front edge and curves downward each side (fig. 232).

Fig. 231 shows a web of the most common form in the corner of a cellar, with the spider standing at the mouth of the tube, and the remains of egg cocoons hung up at the left. This web was at least a year old, and the front edge had just been extended with clear and transparent silk, while the middle was black with coal dust.

Fig. 232 is another web in the same cellar, with the front edge fastened up to the boards above. It is drawn tightest in the middle and curves down on each side.

Figs. 233, 234. Tegenaria medicinalis.—233, adult female enlarged four times. 234, cephalothorax of young female to show spots. Figs. 233, 234. Tegenaria medicinalis.—233, adult female enlarged four times. 234, cephalothorax of young female to show spots.

Tegenaria (CÆlotes) medicinalis.—A large gray spider living in the woods, among rocks, in hollow trees, and under loose bark. It is half an inch long, with the legs of the female not much longer (fig. 233). The head is large and wide, and the eyes cover a little more than half its width. It is a little constricted in front of the legs and raised above the thorax as far back as the dorsal groove. The abdomen of the females is large and oval, widest across the hinder half. The spinnerets are small, but plainly two-jointed, and the upper pair longest. The general color is light yellow brown, covered with gray hairs, the cephalothorax browner, and the abdomen grayer, than the legs. The cephalothorax has two indistinct gray stripes. The abdomen is marked with a series of gray spots of irregular shape, smallest toward the front and larger and darker toward the end. The legs are faintly ringed with gray, more distinctly in the young.

Fig. 235. Palpus of male Tegenaria medicinalis. Fig. 235. Palpus of male Tegenaria medicinalis.
Figs. 236, 237. Two forms of epigynum of Tegenaria medicinalis. Figs. 236, 237. Two forms of epigynum of Tegenaria medicinalis.

The males are as large as the females, with smaller abdomen and longer legs. The palpi have the patella and tibia short, not much longer than wide (fig. 235). The patella has a short process on the outer side near the end. The tibia is of complicated shape, as shown in the figure. The tarsus is twice as long as the tibia and patella together, with a long narrow tip. The palpal organ is large and complicated, with a long fine tube that can be seen from above, where it curves around the base of the tarsus.

Fig. 238. Web of Tegenaria medicinalis in a hollow of a rock, the front edge held up by threads running across the hollow, and the mouth of the tube showing behind it. Fig. 238. Web of Tegenaria medicinalis in a hollow of a rock, the front edge held up by threads running across the hollow, and the mouth of the tube showing behind it.

The epigynum varies in appearance according to the thickness and color of different parts. The two figures show common varieties (figs. 236, 237). This species and longitarsus are both easily mistaken for Amaurobius sylvestris and ferox, which are of the same size and color and live in the same situations. Amaurobius does not have the long upper spinnerets like Tegenaria, the eyes are lower on the front of the head, and there are larger light-colored markings on the front of the abdomen. The young of Tegenaria medicinalis are pale, with light gray markings, and the cephalothorax is marked with spots radiating from the dorsal groove (fig. 234). The web of this spider is not flat like that of Agalena, but curved in various shapes according to the place where it is built. If there is an open level place near the nest, the web spreads across it, but usually curves upward at the edges and is fastened to surrounding stones and weeds. Where the spider lives in the cracks of a wall or rock, the net spreads along the surface of the rock, held away from it a short distance by threads fastened to projecting points on the stone (figs. 239, 240). This species is sometimes mistaken for the longer legged and more hairy Tegenaria derhamii (fig. 228), that makes similar webs in barns and cellars.

Tegenaria (CÆlotes) longitarsus.—Smaller than medicinalis; about two-fifths of an inch in length. The head is very wide, and the mandibles of the female more swelled in front than in medicinalis, and the eyes are smaller and cover less than half the width of the head (figs. 244, 245). The cephalothorax is darker colored in front and does not have the two longitudinal stripes seen in medicinalis (fig. 241). The legs are only faintly marked with gray in the middle of the joints. The abdomen is marked with gray, in a series of dark and light spots, as in other species, and of more regular shape than in medicinalis. The epigynum is light colored, with a middle bar covered with hair and slightly forked at the hinder end (fig. 242). The male differs in the usual way from the female and has the palpi shorter than medicinalis. The tarsus has a projection at the base that covers the tibia. The patella has a short process on the outer side that points directly forward (fig. 243).

Fig. 239. Sections of webs of Tegenaria and Agalena. Fig. 239. Sections of webs of Tegenaria and Agalena.—a, Agalena nÆvia; b, common form of Tegenaria derhamii, with the edge lower than the tube; c, Tegenaria, with the edge higher than the tube; d, Tegenaria, with the edge carried up along the face of a rock; e, Tegenaria, with the edge carried down as well as up.
Fig. 240. Web of Tegenaria medicinalis. Fig. 240. Web of Tegenaria medicinalis, with the front edge carried up along the face of a rock. See diagram (fig. 239, d).
Figs. 241, 242, 243, 244, 245, 246, 247, 248, 249. Tegenaria longitarsus.—241, back of female. 242, epigynum. 243, palpus of male seen from above. 244, head of Tegenaria medicinalis. 245, head of Tegenaria longitarsus. Tegenaria complicata.—246, female enlarged four times. 247, epigynum. 248, 249, male palpus. Figs. 241, 242, 243, 244, 245, 246, 247, 248, 249. Tegenaria longitarsus.—241, back of female. 242, epigynum. 243, palpus of male seen from above. 244, head of Tegenaria medicinalis. 245, head of Tegenaria longitarsus. Tegenaria complicata.—246, female enlarged four times. 247, epigynum. 248, 249, male palpus.

Tegenaria (Cicurina) complicata.—A small spider, resembling the young of the larger species of Tegenaria, found usually under dead leaves in woods (fig. 246). It is a fifth to a quarter of an inch long, with the longest legs one and one-half times as long as the body. The spines of the third and fourth legs are long and stout, and there are long fine hairs on all the legs and the abdomen. The color is pale yellowish brown, lighter on the abdomen, which has faint gray markings. The sexes are much alike, and both vary in size. The palpi of the males are very large and conspicuous (figs. 248, 249). The patella is short and wide, and the tibia is narrower at the end and wide toward the base, where it has a short process on the outer side. On the under side of the tibia is a long thin appendage of irregular shape that is nearly as long as the tarsus. The tarsus itself is long[Pg 104]
[Pg 105]
and narrow, and the palpal organ large and complicated, with a long fine tube that extends from the base along the outer side and back to the hard appendages in the middle. The epigynum (fig. 247) has a small, transverse, oval opening at the hinder end, in front of which the coils of long tubes can be seen through the skin.

In New England AgalenidÆ Pl. VII, fig. 2 is the epigynum of this species and not of CÆlotes longitarsus.

Figs. 250, 251. Hahnia bimaculata. Figs. 250, 251. Hahnia bimaculata.—250, female enlarged twelve times. 251, under side showing the peculiar arrangement of the spinnerets.
Fig. 252. Hahnia cinerea. Fig. 252. Hahnia cinerea, enlarged sixteen times.

Hahnia bimaculata.—The Hahnias resemble Tegenaria, but are much smaller and have the spinnerets extended in a line across the under side of the abdomen (fig. 251). Hahnia bimaculata is about one-eighth of an inch long, with the abdomen large and oval, widest behind, as it is in CÆlotes (fig. 250). The cephalothorax is bright orange brown, and the legs and abdomen pale yellowish with gray markings. The legs are ringed with gray, the longer joints having two rings, and the abdomen has a pattern of light yellow and gray spots. The spinnerets are all long and in a nearly straight line, half as long as the width of the abdomen. The outer or upper pair are half as long as the abdomen, and the two joints are nearly of equal length. The tracheal opening is in the middle of the abdomen, nearer the epigynum than the spinnerets. The sternum is as wide as long, widest opposite the second legs. The maxillÆ are straight in front and have a slight projection at the outer corners, where there are two or three stiff hairs. In some other species there is a longer process at these corners.

This spider is common in winter under stones and under leaves. In summer it makes webs close to the ground, among short and thin grass and moss.

Hahnia cinerea.—About a twelfth of an inch long; much smaller than bimaculata (fig. 251). The color is dark gray, the cephalothorax and legs brownish, and the legs a little lighter at the ends of the joints. The abdomen has a row of angular light spots in the middle. The spinnerets are in not quite as straight a line as in bimaculata, the outer pair being a little higher and farther behind the next. The tracheal opening is not as far forward as in bimaculata, being nearer the spinnerets than the epigynum. The male palpi have the appendages of patella and tibia longer than in bimaculata, and softer and more curved. They are found under stones and leaves.


                                                                                                                                                                                                                                                                                                           

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