824 General Notes. [October, 



fore, that the parent Strongylium had laid eggs at the entrance 

 of a gallery made by a species smaller than itself, and that this 

 mistaken instinct resulted in the death of its progeny in the 

 manner just described. — E. A. Schwarz, Washington, D. C. 



Bacterium a Parasite of the Chinch Bug. — In the course of 

 some experiments made last month upon the chinch bug, I was 

 annoyed by the rapid disappearance of the bugs under observa- 

 tion, which were on some hills of corn transplanted to the labo- 

 ratory. Unable to find any evident cause of the phenomenon, I 

 crushed a number of those remaining alive, and examined the 

 fluids from their bodies under the microscope. In every case 

 these were found to be swarming with a species of Bacterium not 

 easily distinguishable from B. tcrmo. The observations were 

 many times repeated with every precaution against accidental in- 

 fection, but with the same results. Using water freshly distilled 

 and rc-distilled, passing slides, covers and the tools used through 

 the flame of an alcohol lamp at every step of the. operation, I still 

 found the same Bacterium in thousands in every preparation, but 

 much the most numerous, as a rule, in the oldest specimens. 



Careful search in the juices of the corn upon which the insects 

 were feeding, failed to discover anything of the kind there. If a 

 bug were thoroughly washed in a drop of distilled water, no Bac- 

 teria occurred in the water, showing that they were not derived 

 from the surface of the insect. When a number of the bugs were 

 kept for a week in a bottle without food, the Bacteria were found 

 to have greatly increased in numbers, and were especially abundant 

 in those which were recently dead. When the legs and head 

 were cut off in a way to avoid injury to the alimentary canal, and 

 crushed by themselves upon a slide, no Bacteria were found ; and 

 if the thorax and abdomen were crushed on separate slides, that 

 containing the latter showed, as a rule, the greater numbers. 



Careful dissections of the chinch bug were next made, for the 

 purpose of ascertaining whether the seeming parasites could be 

 traced to the alimentary canal. In five cases I succeeded in iso- 

 lating the digestive organs, transferring them to a slide, and 

 crushing them with the covers in distilled water. In all these 

 cases the Bacteria were very abundant, and could be seen issuing 

 from the stomach in adherent masses and also in motion sepa- 

 rately in all parts of the field. In two cases where a comparison 

 could be made between the contents of the anterior and posterior 

 parts of the canal, they were found much the most numerous m 

 that part of the canal posterior to the malpighian tubes. On the 

 other hand, Bacteria were also found in the water in which the 

 dissections had been made; but as it is probable that the intestine 

 was more or less torn in preparing the object, these may have 

 escaped from its cavity. None were found in the ganglia of the 

 nervous system in the only case in which I examined these 



