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 larvag, its length is about the same as that of 

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



OMRTTJM 



Fig. 124. Internal anatomy of a cockroach, Periplaneta orientalis; a, antennae; 

 bi, 6 2 , 6 3 , first, second, and third legs; c t cerci: d, ventricular ganglion; e, 

 salivary duct: /, salivary bladder, g, gizzard or proventriculus : h, hepatic 

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

 intestine: w, rectum; n, first abdominal ganglion; o, ovary; p, sebaceous 

 glands (From Rolleston). 



