SPIDERS, MITES, AND SCORPIONS. 



163 



threads in contact with the victim. At last the spider walks out, ap- 

 proaches rather close to the fly, and pulling out a lot of fresh threads with 

 her hind legs, proceeds to attach them to the fly. Finally, one wing is 

 •firmly pinioned by these silken curds, then the other is fastened, and at 

 last he is capable of no further motion. The spider now conies closer and 

 sinks her venomed fangs in the body of the fly, and all is over. The spider 

 now cuts away most of the bind- 



ing threads, and carries her prey 

 to the nest, where she sits and 

 Micks its blood. 



Another form illustrated in 

 our next cut is remarkable for the 

 sub-aquatic nests that it makes. 

 It crawls clown the steins of the 

 aquatic plants, and proceeds to 

 build a balloon-shaped web, the 

 walls of which are air-tight . "When 

 the nest is complete, the spider 

 climbs to the surface and pro- 

 trudes the tip of its abdomen, 

 and then jerks it down quickly, 

 crossing her legs over it as she 

 does so. A bubble of air is caught 

 among the hairs, and is carried 

 down and allowed to escape into 

 the nest. In this way she gets a 

 supply of air to breathe while she is beneath the surface, where she spends 

 most of her time catching aquatic insects. As the spiders descend, thus 

 carrying air, they appear to be covered with a silver sheen. 



Another use made of spider silk is to form egg-cocoons. The process 

 of forming these is curious but complex. Some of them are scale-like, and 

 are concealed beneath boards or stones ; while others take spherical or even 

 vase-like shapes, sometimes of considerable beauty of outline. One species 

 carries its cocoon about with it, attached to the end of its abdomen, and 

 the young, when hatched, ride upon the backs of the mother much like the 

 young of the opossum. 



Comparatively frequently one sees statements in the newspapers of 

 persons suffering from the bites of spiders, which are sometimes said to be 

 followed by fatal effects. It is extremely probable that in all these cases 

 there is some mistake, for there are but few spiders in the northern states 

 which possess jaws strong enough to puncture even the thinnesl skin. 



Fig. 145. — Water-spider (Argyroneta), and its sub- 

 aquatic uest filled with air. 



