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clusters whicli are found in localities in which Flacherie oper- 

 ates among the caterpillars contain, on the average, a compara- 

 tively high percentage of dead eggs. Hence, Flacherie has a 

 direct effect even upon the next generation. If, however, the 

 number and the quality of the eggs in the female adult are 

 affected by the wilt, is it not then possible that the disease goes 

 directly over to the eggs? Certainly we have no direct proof 

 of this at the present time, but we do know that Flacherie can 

 be carried over from the caterpillar to the pupa, and from the 

 pupa to the adult, and we have seen that the eggs in the ovary 

 of females which come from infected colonies are influenced 

 by the disease in regard to their number and vitality. In spite 

 of the many investigations which have been made by celebrated 

 bacteriologists in both the old and the new world, the carriers 

 of the disease have not yet been determined. This shows what 

 a difficult problem science has before it to solve. Although 

 several scientists accept neither the heredity of the disease, 

 nor believe that it can be carried over to the next generation, 

 there are others (Pasteur, Fischer) who believe in its trans- 

 missibility. Perhaps the disease is carried over to the follow- 

 ing generation through the adult female only, in a similar 

 manner to the pebrine. Perhaps, moreover, the name Flacherie 

 covers several diseases, which, it is true, make their appearance 

 in the same manner in the infected individuals, but neverthe- 

 less are specifically distinct. One of these diseases may be 

 restricted, indeed, to caterpillar and pupa only, while the other 

 disease is carried over to the adult, and might possibly be in- 

 herited through the female organism by the descendants. It 

 may be possible to throw some light on these complicated ques- 

 tions by breeding experiments, but only the investigations of the 

 bacteriologist and pathologist can secure the final proof. It 

 would be of the highest importance for the economic value of 

 Flacherie if the inheritance of the disease could be definitely 

 proved. If the wilt proves to be the direct cause for the " dying 

 off " of many embryos of eggs from infected localities, death 

 would be caused by the organisms of the disease themselves, 

 and probably not be a result of the weak constitution of the 

 female moth. The still living embryos of the same cluster will 



