THE VITAL CONDITIONS OF BACTERIA. 99 



Thermopliilic bacteria: minimum at 40 -49, best 

 at 50 -55, maximum at 60-70. These include many 

 bacteria of the soil, and almost all the sporulating 

 bacilli related to bacillus mesentericus. According to 

 Globig about thirty varieties are still capable of de- 

 velopment at 60, and a few at 70 (Z. H., III., 294). 

 Miquel (Ann. de Micrograph., I., 4; C. B.,V., 281) 

 has described a bacillus thermophilus Miqu., which 

 thrives at from 42-72, best at 65-70, and has its 

 habitat in privies, the intestinal contents, and dirty 

 water. The description is insufficient to distinguish 

 the bacillus. 



Recently Lydia Rabinowitsch. has described eight 

 thermophilic facultative anaerobic varieties; they 

 were all non-motile sporulating rods*, which throve 

 best at 60-70, but proliferated slowly even at 34-44, 

 best in an anaerobic agar culture (Z. H., XX., 163). 

 These varieties are widely diffused, particularly in 

 the faeces, but Rabinowitsch did not make any com- 

 parison with the forms described by previous writers. 



By gradually increasing and lowering the temper- 

 ature Dieudonne (C. B., XVI., 965) succeeded in in- 

 creasing the temperature interval within which the 

 bacillus anthracis is capable of proliferating. The 

 bacillus could be adapted gradually to a temperature 

 of 42. According to the assumption of some writers 

 pigeons are tolerably immune to ordinary anthrax on 

 account of their high temperature (42), but when 

 the bacilli had been adapted to high temperatures 

 the pigeons died more frequently after inoculation. 



Still more striking; were ^heTesults Vh&n DiQiicTonne 



big found unusually narrow ranges for many ihermopliiie varie- 

 ties; for example., oTieform rew\orrly 



