i66 



THE .ANIMALS AND MAN 



many silk-glands in the abdomen, from each of which a 

 fine duct runs to a spinning-tube. 

 The spiders may be divided into two groups according to- 



FiG. 75. The dog- or wood-tick, Dermacentor americanus, male, the most 

 abundant tick in the Northern States. (Natural size indicated by 

 line; after Osbom.) 



their habits, viz., the wandering or hunt- 

 ing spiders, which do not spin webs to 

 catch their prey, and the sedentary or 

 web-weaving spiders, which spin snares to 

 catch their prey. The wandering spiders 

 can spin silk, however, and often do so to 

 Fig. 76. The line their burrows, to make nests, or 

 to make egg-sacs. The hairy tarantulas 

 and the trap-door spiders of similar appear- 

 ance are among the most interesting of the 



eyes and 

 mandibles of 

 a spider. 

 (Much e n - 



Sfnslnd l^™ting spiders. They live in vertical 

 Kellogg.) burrows or tunnels in the ground which 



