THE INTERNAL ANATOMY OF INSECTS 107 



III. THE ALIMENTARY CANAL AND ITS APPENDAGES 



a. THE MORE GENERAL FEATURES 



The alimentary canal is a tube extending from one end of the body 

 to the other. In some larvee, its length is about the same as that of 

 the body; in this case it extends in a nearly straight line, occupying 



a iivnnsa 



Fig. 124. — Internal anatomy of a cockroach, Periplanela orientalis; a, antennas; 

 bi, ^2, 63, first, second, and third legs; c, cerci: d, ventricular ganglion; e, 

 salivary duct; f, salivary bladder, g, gizzard or proventriculus ; h, hepatic 

 coeca; i, mid-intestine; j, Malpighian vessels; k, small intestine; /, large 

 intestine: m, rectum; », first abdominal ganglion; 0, ovary; p, sebaceous 

 glands (From RoUeston). 



