1896.] MICROSCOPICAL JOURNAL. l75 



a narrow unstained or more feebly-tinted band separating 

 the body of the organism from a deeply-stained ring of 

 which the flagella appeared to be projections. This cap- 

 sule-like appearance has been illustrated by several 

 observers. Biitschli, Zettnow and others hold that the 

 part of the bacilius which is easily brought out by the 

 ordinary staining methods is the nucleus only, and that 

 the additional portion of the organism demonstrated by 

 LoefHer's method is plasma which surrounds the nucleus. 

 Haeckle, on the other hand, states that they have no nu- 

 clei. For this and other reasons he refers bacteria to the 

 animal kingdom, placing them in the first class of Arche- 

 zoa. 



Farrier has re(;ently published a series of interesting 

 experiences in which he shows that flagella on a single 

 species of bacteria — as determined by the study of sev- 

 eral forms — are subject to variations according to the con- 

 ditions under which the organism is cultivated. Thus he 

 found that Bacillus coli communis, cultivated at the tem- 

 perature of the body, possessed several flagella, but when 

 grown at a much higher temperature (46°C. maximum 

 temperature for this bacillus) flagella could not be de- 

 tected. If grown at 44°C. a few of the individual bac- 

 teria possessed these appendages. The age of tlie culture 

 and the presence of a non-fatal quantity of an antiseptic 

 in the culture media were likewise found to have apprec- 

 iable effects. He states that this pleomorphism is due to 

 their protoplasmic nature ; the hypothesis assumed being 

 that when the bacteria are subjected to degenerative 

 agencies, such as high temperatures or antiseptics, the 

 plasma contracts in a ball-shaped mass (presumably about 

 the organism), but when the bacillus is again brought un- 

 der favorable conditions the plasma resumes its motile 

 form. 



Accepting this' explanation, it is difficult to understand 

 why the motile bacteria possessed of cajisules such as 



