230 Annals Entomological Society of America [Vol. XIII, 



wall of the anterior crop is thin and has its epithelium poorly- 

 developed, this does not imply that there is any connection 

 with the tubes which coil above this region. The anterior 

 crop receives no tube, other than the esophagus, nor does it 

 give off outgrowths in any part. 



It was stated previously that the descending intestine, 

 arising from the left anterior part of the "internal gland, " looks, 

 in a dissection, as if it might be a posterior continuation of 

 the esophagus. Sections do not confirm this possibility. On 

 the contrary, a frontal section (Fig. 7) shows the descending 

 intestine to be continuous with the ascending intestine. The 

 latter enters the internal gland posteriorly and runs forward 

 to its anterior margin. A comparison of sections in three 

 different planes proves, then, that the enlargement in the 

 metathorax is composed of two distinct parts — a dorsal, tubular, 

 closely-wound mass made by the ascending intestine and 

 malpighian vessels, and a ventral distensible portion con- 

 tinuous with the esophagus. 



The posterior crop neither receives nor gives off any out- 

 growths until its extreme posterior end is reached. Sections 

 show (Fig. 14) that it empties directly into the narrow ascending 

 intestine which then proceeds in a general anterior direction 

 to join in the formation of the internal gland, as previously 

 described. A muscular ring or valve is found at the junction 

 of the last mentioned parts. 



There are four malpighian vessels. They are easily found 

 in any section between the crop and rectum. They are not 

 easily distinguished in dissections since they are almost the 

 same in color as the fat which surrounds them. Their diameter 

 is about half that of the intestine. The blind ends of the 

 tubules lie in the extreme posterior end of the body. They 

 run forward in irregular fashion, mostly dorsally, until they 

 approach the region of the anterior crop. Here they describe 

 a short loop just above the internal gland and then disappear 

 into it at its posterior margin. 



From the foregoing descriptions it is clear that if plant 

 juices are taken in as food, they are conveyed to the anterior 

 crop directly through the esophagus. They then pass to the 

 posterior crop which, in all probability, functions as a storage 

 sac as well as contributing to the digestive process. From 

 the posterior crop the liquid food passes into the ascending 



