238 



otlier spinneret, but these tubes are much liner. These spiders 

 have also on the next-to-the-last segment of the liind legs one or 

 two rows of curved spines ; this organ is the calamistrtcni (Fig. 127). 

 By means of the calamistrum these spiders comb from the cribellum 

 a band of loose threads wdiich form a part of their webs. 



The Curled-thread Weavers. 



The spiders possessing a cribellum and a calamistrum represent 

 two families, one of which makes irregular webs ; the other, those 

 which are of definite form. 



An irreirular web of a curled-thread weaver is shown in Y'm. 128 

 fro!n a photograph. In this web the framework is of 

 ordinary silk ; and upon this framework is placed a band 

 of curled or tangled threads (Fig. 129). An insect 

 aliofhtino: on a net of this kind is likely to a'et its feet 

 Vr^Q.— l^rafj- (>^^^gjj|; jjj ^\^Q tangled silk, and to be held in fast till the 



curled- spider can pounce upon it. Nets of this kind are found 



t hread on bushes and on the sides of buildings. 



iceaver's There are two quite distinct types of regular webs 



web, en- ,^j^^g \^y spiders possessing a cribellum and a calamis- 

 trum. One is a round web which resembles at lirst 

 sight those of the orb w^eavers ; but it differs from the ordinary 

 orb-web in that the spiral thread is made of curled or hackled silk. 

 These webs are nearly horizontal, and are usually made between 

 stones or in low bushes ; they are not common. 



The other type is represented by the web of the Triangle 

 Spider. This web is most often found stretched between the twigs 

 of a dead branch of pine or hemlock. At iirst sight it appears like 

 a fragment of an orb-web (Fig. 130) ; but a little study will show 

 that it is complete. The accompanying figure, by Dr. B. G. 

 AVilder, who first described the habits of this spider ("Popular 

 Science Monthly," 1875), illustrates the form of the web. It con- 

 sists of four plain lines corresponding to the .radiating lines of an 

 orb-web, and a series of cross lines, which are spun by the cribellum 

 and (udamistrum. Each cross line is composed of two lines about 

 yj J of an inch apart, These double lines take the place of tliQ 



338 



