AND PHYSIOLOGY, 19t 



Fig. 200. 



Digestive Organs of Ammothea pycnogonoides (Crustacean), a. Esophagur b. Stom* 

 ach. c Intestine, d. Digestive Cavity of the Jaws. e. Digestive Cavity of the Legs. 



powerful set of muscles, which help in the reduction of the 

 food. These teeth are found in the Lobster's stomach. The 

 stomach of the Leech is very capacious, being nearly the size 

 of the whole body. The same is essentially true of the com- 

 mon Earthworm, which is an Annelid. In many insects 

 salivary glands are present, and in such cases they are placed 

 at the commencement of the alimentary canal. The different 

 parts of the alimentary canal in insects " may be properly 

 distinguished in the following manner. The first portion is 

 the Esophagus, muscular, occupying the three thoracic seg- 

 ments and often dilated at its posterior part into a crop 

 (Ingluvies) and muscular gizzard (Proventriculus). Some- 

 times there is appended to the Esophagus a sucking stomach, 



