PHYSIOLOGY OF THE INVEKTEBRATA. 



7B 



B. 



C. 



Fig. 19. — Alimentary Canal of Helix aspeksa. 



a = mouth. d = odontophore. r — tooth. c/ = buccal mass^ 

 ^ = oesophagus. /= salivary duct. "^ = salivary gland. //= rectum.. 

 i = crop or proventriculus. i = intestine. / = liver, m = stomach. 



Buccal Mass. a = tentacle (optic organ). /' = tentacle (olfactory 

 organ ?). c = horny jaw. </ = mouth, c = lateral lip. / = cir- 

 cular lip. 



Longitudinal Section of Buccal Mass. a = odontophore. /> = ra- 

 dular membrane, c = odontophore cartilage. (/ — intrinsic muscle. 



