376 



COLLEGE ZOOLOGY 



ment in different species. Spiders apparently can see objects 

 distinctly only at a distance of four or five inches. 



The sexes are separate, and the testes or ovaries (Fig. 314, 13) 

 form a network of tubes in the abdomen. The spermatozoa are 



FIG. 317. A, crab-spider, Thomisus. B, jumping-spider, Attus. C, young 

 spider, Lycosa, preparing for an aerial voyage. D, house-spider, Theridium 

 epidariorum. (A, B, C, from Davenport, after Emerton ; D, from Emerton.) 



transferred by the pedipalps of the male to the female, and fer- 

 tilize the eggs within her body. The eggs are laid in a silk co- 

 coon, which is attached to the web or to a plant, or carried about 

 by the female. The young leave the cocoon as soon after hatch- 

 ing as they can run about. 



The spinning organs of spiders are three pairs of appendages 

 called spinnerets (Fig. 313; Fig. 314, 18). The spinnerets are 

 pierced by hundreds of microscopic tubes through which a fluid 



