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The Chinch Bug Bntomopthora — In a number of the agricultural jour- 

 nals during the past summer, items have appeared referring to the 

 experiments being conducted by Prof. F. H. Snow, of the Kansas State 

 University, in the intentional dissemination of this disease. We notice 

 in the October 2d issue of the Lawrence (Kan.) Daily Journal a long 

 account of the success of the experiments, in which letters to Pro- 

 fessor Snow are quoted at length and which thus bear the impress of 

 his sanction. It is stated in this article that Professor Snow obtained 

 some bugs killed by the Entomopthora, and mixed them with live bugs 

 which were soon attacked and died. Bepeating this experiment until 

 he had a sufficient number of dead bugs on hand he distributed them 

 in small batches to various farmers, agricultural experiment stations, 

 naturalists, and others — in all, to about fifty persons. Each lot was ac- 

 companied with directions to collect ten to twenty times the number of 

 healthy bugs and mix them with the diseased bugs for thirty-six or 

 forty-eight hours, and then turn them loose in the field and watch closely 

 for the result. The letters published are mainly from agriculturists 

 and are favorable. In other words, all the published answers state that 

 the disease seemed to have been communicated. 



Ever since Prof. O. Lugger published his apparently favorable re- 

 sults in the same direction, something more than a year ago, we have 

 watched the accounts of subsequent attempts, and endeavored to ascer- 

 tain whether any thoroughly scientific evidence of the spread of the 

 disease has been established. The matter is of sufficient importance 

 to require the most careful weighing of the evidence, as the apparent 

 evidence is so easily misconstrued, and the danger of unjustified state- 

 ment and assertion is so great. In this particular article we notice 

 that no dates are given to the letters, and that the correspondents in 

 no way show that the supposed healthy bugs were examined critically, 

 the evidence of life being assumed to mean healthfulness. The chief 

 difficulty is that at the time when the disease is prevalent in one local- 

 ity the same climatic and zymotic conditions are liable to — and in fact 

 usually do — prevail through a wide extent of country, and that the dis- 

 ease, if it has not already appeared, may be about to appear over the 

 whole area. This at once establishes the necessity of the most careful 

 observations by means of check experiments. If the diseased bugs are 

 simply placed among apparently healthy bugs and the latter subse- 

 quently become diseased, the proof of direct transmittal by contagion 

 is but negative. If, however, healthy bugs are isolated from the im- 

 ported diseased bugs and remain healthy, then a probability is estab- 

 lished in favor of the contagion by contamination. The disease is 

 always most prevalent in cool, wet weather, from midsummer on, when 

 large numbers of the older bugs are naturally dying from other causes, 

 and are probably more liable to fall victims to any scourge of this kind. 



The subject is of extreme interest, and while there are reasons which 

 would make us doubtful of any tangible and practical results following 



