MICROSCOPIC ORGANISMS IN INTESTINAL CANAL. 245 
boiling is complete and permanent, an abundant development of 
bacteria almost invariably afterwards occurs, even in cases where 
the greatest precautions are taken to secure the exclusion of ex- 
trinsic elements. The following notes were recorded of the phe- 
nomena in one case of this kind :—A portion of normal excreta 
Fic. 2.—Excretal Bacilli x 1000. 
was boiled for half an hour, and set whilst boiling in a moist 
chamber. This remained closed for forty-eight hours, and the 
specimen was then examined. ‘The reaction was alkaline, and 
the surface of the medium was found to swarm with minute 
active bacilli (Fig. 2). On the following day the majority of the 
bacilli had passed into the still condition, and formed a thick, 
grey, creamy layer covering the surface. The individual rods 
measured about 3°5 in length. They were either scattered 
singly or were associated in series of two, three, and sometimes 
of four. Their breadth was about 0°92. Many of the still 
Fic. 3.—Bacilli passing into spore formation x 1000. 
ones had already passed on into spore formation, and in doin 
so seemed to become somewhat shorter and thicker (Fig. 3). 
Subsequently the whole of them assumed this condition, and 
ultimately the bacillar coating was replaced by a thick gelatinous 
layer of the free spores. No traces of Ozdiwm or of other fungi 
ever manifested themselves. 
During the great increase of acidity occurring coincidently 
with the development of Oidium the zoospores rapidly become 
motionless, disintegrate, and disappear. The rate at which they 
do so is curiously rapid. Frequently within an hour a portion 
of the material, which at first showed numerous characteristic and 
active zoospores, retains no recognisable traces of their presence, 
and im some cases a period of ten minutes is sufficient to produce 
most marked changes. That this effect is not to be ascribed to 
