THE SNAIL 



75 



an. 



A dissection of Helix aspersa from the dorsal surface. The roof of the mantie- 

 cavity has been cut through near the collar and thrown back ; the generative 

 organs are displayed on the left, and the alimentary tract on the right of the 

 figure, al, albumen gland ; an, anus ; au, auricle ; l>u, blood-vessels in 

 mantle ; c^, cerebral ganglion ; cr, crop ; ftil, globular dilatation on sperma- 

 theca; div, diverticulum of spermatheca ; Ds, dart sac ; gl, glandular part 

 of excretory organ ; hd, hermaphrodite duct ; /?, flagellum of penis , int, 

 intestine ; //, liver ; Mg, mucous glands ; od, oviducal portion of conjoined 

 genital duct; ov, oviduct; ot, ovotestis ; /', penis; pc, pericardium />h, 

 pharynx ; R, rectum ; si/, salivary glands ; sd, duct of salivary gland ; sf>d, 

 sperm iducal portion of conjoined genital duct ; spth, spermatheca ; ur, 

 ureter ; z/, ventricle of heart ; vd, vas deferens. 



