ZOOLOaY AND BOTANY, MICROSCOPY, ETC. 89 



showing for each month the quantity of spores in the air of Mont- 

 souris, and describes some interesting facts concerning the cultivation 

 of bacteria. 



Bacillus urece, cultivated in neutral bouillon, falls to the bottom 

 of the vessel, and dies, leaving the liquid perfectly transparent ; but 

 if a little pure larea is added when the parasite is living, the fluid 

 becomes cloudy and charged with carbonate of ammonia. Of all the 

 species cultivated by the author in a state of purity, none abandoned 

 their special aptitudes nor departed from the cycle of evolution 

 proper to each. Certain illusions and analogies are therefore to be 

 guarded against. Bacilli, in the absence of oxygen, can assume a 

 resemblance to Bacteria, and Bacteria when dead are easily confounded 

 with Micrococci. 



Pathogenous Bacillus in Drinking Water.* — J. Brautlecht has 

 detected in drinking water, which was considered to be the partial 

 cause of an epidemic of typhus, a bacillus which he cultivated in a 

 solution of 3 per mil. gelatine in spring water, with 25 per cent, 

 ammonium phosphate. This was distinguished from other non- 

 pathogenous bacilli by the absence of any powerful reducing action 

 and also of the offensive odour of some other species ; having a 

 pleasant odour somewhat like that of boiled milk. This bacillus 

 forms filaments in the nutrient fluid, which soon break up into short 

 rods, which separate into cocci loosely connected in a moniliform 

 manner. In later cultures only rods and cocci were visible, which 

 did not exhibit any spontaneous motion. Besides the suspected 

 drinking water, a bacillus with the same characteristics was found in 

 the urine of typhus patients, also on the surface of thick masses 

 of putrefying algae. When inserted beneath the skin of a rabbit, 

 these bacilli caused violent fever in from 18 to 36 hours. 



Connection of Diseases with specific Bacilli.t — H. Buchner 

 describes a series of experiments for the purjDose of determining 

 whether contagious diseases are caused entirely by the bacill l wliic h 

 are found to accompany them, or whether the action of t'lese is 

 assisted by a peculiar chemical substance resulting from the diseased 

 tissue. The results pointed entirely in the direction of the first of 

 these hypotheses. It was found in the first place that the cattle 

 disease was produced by bacilli originally taken from diseased 

 subjects, even when these had been cultivated to thirty-six genera- 

 tions, when it was impossible for the least trace of any disease-producing 

 substance to exist which had come directly from the diseased subject. 

 In the second place, it was found, after repeated and long-continued 

 culture, that these disease-producing bacilli differed in no visible 

 respect from the bacilli produced spontaneously in hay ; while with 

 the latter he was able to produce the disease by injecting it into the 

 blood of white mice and rabbits. 



* Virchow's Arch. path. Anat., Ixxxiv. p. 80. See Naturforscher, xiv. (1881) 

 p. 320. 



t ' Zur Aetiologie der Infectionskrankheiten,' 1881, pp. 69-94. See Bot. 

 Centralbl., vii. (1881) p. 237. 



