1910] Anatomy of Cecidomyiq resinicoloides 53 



glands of the Cecidomyid larva determines the gall. No gall 

 is formed in the case of the pitch-inhabiting midges, but the 

 salivary secretion in this case might well stimulate and maintain 

 the resinous exudation. 



Attached interiorly to the second ampulla of the salivary 

 glands and stretching in a curve across the brain which it overlies 

 very closely is a curious, loose ill-defined structure of granular 

 appearance, F, Fig. VII, PI. 2, and containing brown patches, 

 especially towards the bases. This I believe is Weismann's 

 "cell chaplet," which he defines thus: "It consists of a string of 

 large cells closely united which hangs like a garland, free in the 

 body cavity. Its two ends are connected with the salivar}^ 

 glands," etc. What its function is remains to be ascertained. 



The Malpighian tubules are of a deep orange color and arise 

 from the anterior end of the ileum immediately where the latter 

 is joined to the ventriculus by a delicate membrane. The 

 arrangement of these two tubules with regard to the ileum and 

 colon is not symmetrical since the left one follows rather closely 

 those two divisions of the proctodaeum, while the right tubule is 

 quite free. Fig. 5, PI. VII shows the left tubule in its relation to 

 the proctodaeum. Arising from the ileum each tube proceeds 

 dorsally but not quite in symmetry as the right tube bends anter- 

 iorly and outwardly while the left first curves somewhat poster- 

 iorly, P, Fig. I , PI. VII and then follows the common course. Each 

 tube is closely appressed to the ventriculus to which it is slightly 

 fastened and proceeds anteriorly past the middle of segment 7. 

 Here however the left one by reason of its posterior bend does 

 not reach quite so far forward as its mate, but terminates slightly 

 farther posteriorly and ends somewhat beyond the middle of the 

 colon. Both tubes run along the ventral tracheal trunks in their 

 terminal portions. 



Giard says (10): — "In all the larvae of the Cecidomyidse 

 which I have studied, these tubes, two in number are united into 

 an elegantly recurved handle, and open near the anus, the 

 proctodeum being excessively short." In C. resinicoloides the 

 tubes end freely, as we have seen, and the proctodaeum, if 

 extended would probably at least be as long as the rest of the 

 alimentary canal. 



It may be well said here that the alimentary canal (and its 

 appendages) of C. resinicoloides much resembles that of Diplosis 

 hnxi illustrated by Berlese (2). 



