130 ANATOMY AND PHYSIOLOGY 



being sufficiently masticated. The part last 

 otherwise called the gullet, (PL II. figs. 2, 3, a,; is a 

 narrow tube intermediate between the pharynx i wnen 

 such exists,) and the crop, or, in the absence of the 

 latter, the gizzard. It commonly passes through the 

 thorax in a straight line, and terminates at the origin 

 of the abdominal cavity ; but nothing can be more 

 variable than its length. In certain Hymenoptera, 

 ( Pimpla, PompiluSt) it forms more than half of the 

 entire canal; in the cockchafer, (PL II. fig, 3, a,] 

 a small portion behind the head, scarcely one-sixtietl 

 of its length ; and all intermediate dimensions occur 

 The esophagus is in all cases simple, except among 

 the Lepidoptera, which present the remarkable pecu 

 liarity of a bifurcation anteriorly, a branch emanating 

 from each of the two spiral sucking tubes and uniting 

 into one conduit, usually just behind the head. The 

 crop, (PL II. figs. 2, 3, b, ,) has been so named by 

 Cuvier, Leon Dufour, and Strauss, because it occupie 

 the same position as the organ so called in birds ; b; 

 some other authors it is denominated the stomach 

 It appears, for the most part, as a simple dilatation o 

 the hinder part of the esophagus into a kind of bag 

 which is usually on a line with the other parts of the 

 alimentary canal, but sometimes appears suspended 

 at the side like a pouch. Its form is most variable, 

 even in the same species, according to the degree of its 

 repletion or vacuity. When the gizzard, the succeed- 

 ing portion of the canal, is wanting, which is very 

 often the case, the crop appears in its simplest form, 

 and is unprovided with any secretion to act upon the 



