432 ALEXANDER PETRUNKEVITCH. 



sense primitive. For this reason it cannot be possibly main- 

 tained that B. ovigerus and L. oophorus have simply dropped the 

 habit characteristic of their respective families and reverted to a 

 more generalized and fundamental habit original with all spiders. 

 The conclusion is inevitable that in the course of evolution, 

 before any morphologically considerable changes have occurred, 

 our two species of spiders have modified their habit. 



