200 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



upon which the entanglement had occurred is quite cut away. The spider 

 thereupon proceeds to operate the remaining parts of her snare, which, in 

 time, is thus destroyed by sections, as will be fully illustrated hereafter. 



The second mode of operation resembles that of the Triangle spider, 

 Hyptiotes cavatus (Hentz). It is at this point that the liabit of our Ray 

 spider becomes particularly interesting. The Triangle spider makes a tri- 

 angular web, which is in fact an orb sector, composed with 

 Resem- unvarying regularity of four spirally crossed radii converging ap- 

 „ . proximately upon a single line. Upon this line the spider hangs 

 back downward, grasping it with all her feet, and having a por- 

 tion of the line rolled up slack between her two liind pairs of feet. Tlius 

 the forward and back parts of the trapline are taut, while the interme- 

 diate part is slack. The spiral parts of the snare are also taut. When 



the web is struck by an insect, 

 the spider suddenly releases 

 her hind feet, the slack line 

 sharply uncoils, the spider 

 shoots forward, the whole web 

 relaxes, and the spiral lines 

 are thrown around the insect. 

 This is repeated several times 

 before the prey is seized. (See 

 description and cuts in Chap- 

 ter XI.) 



Precisely the same action 

 characterizes the Ray spider. 

 Her ordinary position, or at 

 least the one in whicli I most 

 ■ frequently observed her, is a 

 sitting posture, back upward, 

 rays are held in the third and 



Fig. 194. Eay spider (greatly enlarged) in position, back down- 

 ward, on a taut snare. To show the slack line coil, SI. The 

 positions of the feet on the foot basket are marked by nu- 

 merals ; a, b, c, the axes of several rays. 



Posture 

 on the 

 Snare. 



as shown at Fig. 187. The axes of the 

 fourth pairs of legs, the fourth commanding the upper, the third the lower 

 series, quite habitually, as it ap})eared to me. A sort of " bas- 

 ket," or system of connecting lines, shown at Figs. 187, 195, 

 unites all the feet, seeming to converge toward the fore feet (per- 

 liaps, upon the second pair), whore they grasp the trapline. It 

 is upon this foot basket that the spider sits when her net is bowed. 



This, however, is not the invariable posture ; in the reconstruction of 

 the rays and shifting of the axes, as the day's work tells upon the snare, 

 the spider will vary her posture to that of Fig. 191. The trapline gen- 

 erally has a direction downward rather than upward, so that the head 

 and fore feet tend to be depressed below the abdomen. Figs. 192, 193, 

 and this depression may gradually result in the comi)lete inversion of 

 the animal, so that she assumes the natural position of Orbweavers. I 



