944 Transactions of the Society. 



appeared vigorous, and not to have suffered in any perceptible way 

 by this unnatural food under their captivity, nor did the culture, as 

 far as could be judged, have any temporary ill effect upon them, 

 save the increased amount of oily globules, which I had learned to 

 regard as indications of progressive debility. All the insects fed 

 often off the moistened sugar, and only a few of the pollen-grains 

 had been partially digested. The insects were killed by the vapour 

 of chloroform, and were not examined. Fari 'passu with these ex- 

 aminations, the dejections of those fed with the anilin dyed sugar 

 were daily examined, but no curved bacilli were noticed in their 

 excreta. The two insects seemed perfectly well, and on the 25th 

 were allowed their liberty. No attempt was made to cultivate the 

 curved bacillus from any of the dejections. 



On the 3rd of August, a large female blow-fly was put in captivity 

 under a similar arrangement. It was at once fed with sugar 

 moistened with a watery solution of methyl-violet. This was 

 damped daily until the 9th with a drop of freshly boiled distilled 

 water. The first dejections had a few long non-motile rods of 

 medium size with blunt ends, a few thick short rods, and here and 

 there a small fine straight rod, averaging in length the 1/10,000 in., 

 abundant micrococci, and a few conidia probably of Fenicillium, 

 faintly stained. All the organisms diminished rapidly in number, 

 and an abundance of narrow acicular crystals and minute oily- 

 looking globules were noticed, the former closely resembling a 

 bacillus, but unstained. On the 9th the fly appeared to be very 

 weak, if it fell on its back it could scarcely rise. This was attri- 

 buted to some detrimental action of the anilin dye, and it was feared 

 the attempt to destroy all the organisms by it had been carried too 

 far, and nearly killed the insect itself. When the vessels were 

 changed it was fed off sugar damped with the gelatin culture of 

 the comma bacillus, the same as was used for the other insects. 

 The culture was much broken down, but contained plenty of the 

 commas. The fly was watched to feed for more than ten minutes 

 without cessation. The last dejection before the change of food 

 was quite liquid, and the few organisms present only faintly stained, 

 the oily globules being very abundant. Fearing the culture might 

 not be well suited for the condition of the fly, it was changed for a 

 fresh lump of sugar moistened with the culture from one of the 

 agar-agar tubes, which abounded in the curved bacillus, and was 

 not broken down like the other. The culture was diluted on the 

 sugar, as it seemed scarcely fluid enough to carry the organisms 

 into the interstices. The same forenoon, a male blow-fly was 

 captured and put with the female fly, both were watched to feed off 

 the sugar frequently but not for long periods. A few hours, about 

 six, after feeding on the gelatin culture, there were six dejections 

 found on the square of glass. They had fairly dried before ex- 



