188 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



the radii was also very large. The space between the several radii, meas- 

 ured at the termination of the spiral space, was about equal in all to one 



and seven-eighths inches. Across 

 the snare at the beginning of the 

 spiral space the distance was one- 

 half inch in all. 



When the web is completed, 

 the spider takes a position upon 



the trapline, sometimes 

 Position i ,i 



f .-, very close to the apex, 

 of Spider, J 



but more frequently 



removed from it by a varying 

 space. Sometimes she is close 



FIG. 179. Position of Hyptiotes on her trapline, T. The coil, to the apex, at Other times Well 

 cl, is shown in the upper figure, and at si in the lower. removed t heref rOlU ; Sometimes 



she hangs upon the line between the apex and the branch to which the 

 line is suspended, and again is found close up to the branch, even rest- 

 ing her abdomen against it. 



II. 



The position of the spider upon her trapline is very peculiar, and 

 worthy of careful study, for it gives a clue to the curious phenomenon 



which is now to be described. Her face and fore feet are 

 Using- tne^ owar( j s j^j. triangular snare. The trapline is held within the 

 N , first two pairs of claws, which are placed near each other (see 



Fig. 179, upper figure), and is drawn so tightly that every por- 

 tion of the wedge shaped 

 web is perfectly taut, as rep- 

 resented in Fig. 180. Upon 

 applying the lens to the 

 spider as she thus hangs 

 with back downward, it will 

 be seen that between the 

 second pair of legs and the 

 third pair of legs, the line 

 is also taut. This is its 

 condition according to most 

 of my observations, but it 

 seems that sometimes it is 



- . FKJ. 180. Hyptiotes' snare drawn taut. 



slightly slackened, as shown 



in the lower figure in the cut. (Fig. 179.) Carrying the lens along to 

 the short third pair of legs we see that they are bent at the knee, and the 

 claws approach each other at the trapline, which they firmly clasp. Glanc- 

 ing at the fourth or hind pair of legs, it is observed that these are stretched 



