Bacteria Kormal to Digestive Organs of Hemipteraj. 7 



I have no present desire to speculate concerning- the 

 meaning- of the bacterial contents of these glands, but 

 limit myself to this preliminary account, and await the 

 completion of the several investigations in which we are 

 now engaged,— upon the distribution of the coeca, their 

 variations, and their relations to the habits of the spe- 

 cies possessing- them, and upon the kinds and nature of 

 the bacteria constantly harbored by these interesting- 

 appendages of the alimentary canal. 



Concerning- their relations to insect disease, I will only 

 add that in chinch bugs perishing gradually but rapidly, 

 we find them varying considerably in number in the coeeal 

 appendages; and that w'here they are most abundant, 

 the epithelium of these structures is completely disorgan- 

 ized, only the basement membrane remaining, in the 

 form of coeeal tubes filled with a pure culture of Micro- 

 coccus insectoriini and a little granular debris, the latter 

 apparently the product of the decomposition of the epi- 

 thelium. 



