Plate IV. 



Vol. IV. 



Helix aspersa. — i, Jaw. 2, Teeth. 3, Dissection showing reproductive 

 organs. 4, A portion enlarged ; a, penis sheath ; b, oviduct ; c, duct of 

 spermatheca. 5, Salivary glands (nat. size) on the sesophagus. 6, One gland 

 and duct enlarged. 7, Esophagus above salivary glands. 8, A bundle of 

 mucous glands, x 2%. 9, Dart in situ. 10, Dart, x 3 with sections. 11, 

 Oblique section of dart (enlarged). 



