THE ORGANS OP NUTRITION. 135 



stomachs. The remainder of the intestine is continued at the opposite 

 side of the stomach, and it is there also that the biliary vessels empty 

 themselves. 



Thus much upon the form of the stomach in the several orders of 

 insects ; with respect to its structure, almost all that can be said upon 

 it has been mentioned above, in treating of the nutrimental canal. The 

 three membranes described there are found also in the stomach, and 

 here particularly distinct. They are here more loosely united than in 

 any other portion of the intestinal canal, and their exhibition is conse- 

 quently attended with no difficulty. The middle membrane is attached 

 more closely to the innermost, and the granules are found in it which 

 Straus (see above, 96.) indicated as gastral glands; between this and 

 the inner mucous membrane the chyle collects, and then transuding 

 through the latter, it enters the abdominal cavity, undulating about all 

 the organs. 



But little also can be said of the situation of the stomach, as it is not 

 subject to much deviation ; it is always found in the abdomen, whilst 

 the oesophagus, and very generally the crop, are seated in the thorax. 

 As soon, therefore, as the intestinal canal enters the abdomen it becomes 

 the stomach, and frequently, indeed, even in the thorax (Melolontha 

 and many others). If the intestinal canal be only as long as the 

 body, the stomach then lies directly in its axis, but if it be longer, 

 it then makes windings, which are the larger and more numerous 

 the longer and more extended it happens to be. These convolutions 

 generally lie in the anterior portion of the abdomen, encompassed and 

 retained in their place by the ramifying branches of the air vessels, the 

 hinder portion being chiefly occupied by the sexual organs ; the stomach 

 and intestine also approaches closer to the back, the internal sexual 

 organs filling the ventral portion, or the space beneath the nutrimental 

 canal. 



106. 



THE DUODENUM. 



The divisions of the nutrimental canal which follow the stomach are 

 generally more simple than the preceding, and also subject to fewer 

 changes of form. In breadth they do not generally, with the exception 

 of the last, or colon, equal that of the stomach ; they are mostly nar- 

 rower, and also more delicately constructed. This entire intestine also 

 consists of the three membranes, which, however, often lie more closely 



