1S91.] MICKOSCOPICAL JOURNAL. 249 



insects which are aheuch artected by the disease in question. The 

 first step of any really scientific investigation of the economics of this 

 matter is to determine positively the absence of the disease in the lots 

 of insects to be used in the experiments. Every lot of chinch bugs 

 thus far obtained by me from central, south-central, and northern Illinois 

 during the months of July and August of this year gave evidence under 

 critical study of the presence of this microbe in the coeca of a larger 

 or smaller percentage of pupie and imagos. My previous observations 

 — less carefully made, however, than my recent ones — have been to the 

 general efibct that hibernating chinch bugs and young preceding the 

 so-called pupa state are little liable to the spontaneous occurrence of 

 the intestinal trouble, and I consequently do not despair of finding be- 

 fore the present season is over opportunity for experiments which will 

 determine beyond question the economic value of this chinch bug 

 ''cholera." 



In comparing this with similar human diseases we must take account 

 of the poverty of the circulatory fluid of the chinch bug and the sim- 

 plicity of its circulatory apparatus, which forbid the marked develop- 

 ment of any of the phenomena of fever or inflammation. Indeed, it 

 seems to me that insect diseases generally are characterized by the ab- 

 sence of a vigorous physiological reaction which their relative!}' lowly 

 structure, nervous and circulatory, makes impossible. The features of 

 this disease, for example, I think may be wholly accounted for, consist- 

 ently with the physiology of the insect, as results of the simple destruc- 

 tion of the epithelium of the co'ca and the consequent suppression of 

 the functions of those organs, combined with the toxic effects of the pro- 

 ducts of bacterial action. 



Is it not quite possible that the student of pathology may find in the 

 study of the diseases of these lower forms of life experiments prepared 

 for him by Nature which it would be quite impossible for him to imi- 

 tate on animals of more complicated sensitive and sympathetic organi- 

 zation, and that he may thus sometimes simplify a problem whose com- 

 plexity must otherwise prevent its solution ? — A^ Am. Practitioner. 



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The American Postal Microscopical Club announces that ar- 

 rangements for tlie resumption of the circulation of its boxes are now 

 progressing. It is desired that changes of address and other business 

 relating to the membership or organization of circuits be at once re- 

 ported to Dr. Ward, the resident manager, at 53 Fourth street, Troy, 

 N. Y. And a more strict conformity to all the rules of the Club than 

 has characterized the past is bespoken for the coming year. The work 

 circulated this year will doubtless be of an improved character, since 

 not only have the poorer of the slides circulated last season been with- 

 drawn, but the special series of slides contributed by members in ..e- 

 sponse to last year's call have been reenforced by a considerable supply 

 of fine foreign work purchased abroad during the summer. 



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Notice. — Messrs. J. W. Queen & Co., of Philadelphia, oculists and 

 opticians, and manufacturers of scientific instruments, have transferred 

 their entire plant, formerly located at 934 Chestnut street, to the larger 

 building, loio Chestnut street. 



