362 Illinois State Laboratori/ of Natural History. 



A tomato-worm (Protoparce) nearly full grown was 

 smeared along the line of spiracles with the diseased 

 fluids. Suitable food could not be obtained, but the larva 

 lived ten days, and gradually shrank in size and partly 

 pupated. At this time a microscopic examination was 

 made, but no bacteria could be found in the tissues or 

 in the fluids. 



Following the above, a larva of the white-lined morn- 

 ing sphinx. Deilephila lineata Fab., was inoculated h\ 

 clipping off its horn and injecting into the body a small 

 quantity of an infusion from a pure culture. The larva 

 died in two days, filled with bacteria of several kinds, 

 and four squash-bugs were then inoculated from this 

 larva. At the end of two days one of these bugs was 

 dead, but the others remained healthy. 



The evidence certainly indicates that this bacillus is 

 not very effective on any insect yet experimented on out- 

 side the order Hemiptera, and that the disease it causes 

 is not likely to be confused with any disease previously 

 described. The growth characters alone, indeed, would 

 serve to distinguish the organism specifically. 



TOXIC PKOPERTIES. 



From one of the early isolation cultures I removed 

 several colonies of the disease bacteria from the surface 

 of the agar, and diffused these in a small quantity of 

 distilled water to serve some inoculation purposes. On 

 immersing young squash-bugs in this infusion, death fol- 

 lowed almost immediately. With nymphs somewhat 

 older the effect was not so rapid, but the bugs soon 

 succumbed. Young chinch-bugs, flies, and other insects 

 stiffened as if dead on being immersed from one to sev- 

 eral minutes. Many of the hai'd-shelled insects, if re- 

 moved immediately on becoming rigid, recover in a few 

 minutes sufficiently to crawl away; but even these die 

 if immersed in the infusion for some time. 



The rapid action of these infusions suggested that 

 somi' y)oisonons pi'iii(i])lo was excreted by the bacteria, 



