40 The Structure and Habits of Spiders. 



abdomen. Each tube is the outlet of a separate 

 gland. Fig. 18, a } shows four small tubes from 

 a spinneret of Epeira, each with a small gland 

 attached; and Fig. 18, b, a large tube, with one 

 of the large glands which extends forward the 

 whole length of the abdomen, Fig. 5, u. 



Fig. 17. 



Fig. 18. 



The shape of the spinnerets, and size and 

 arrangement of the tubes, vary in different spe- 

 cies. Fig. 19 is a spinneret of ProstJicsima, 

 where there are a few large tubes in place of 

 many small ones. In Agalcna the two hinder 

 spinnerets are long, and have spinning-tubes 

 along the under side of the last joint, Fig. 20. 



