ZOOLOGY AND BOTANY, MICROSCOPY, ETC 69 



of the organism that the gas-producing property in the presence of 

 certain test-substances is reduced or entirely lost, and in certain cases 

 the acid-producing property is also diminished. The author discusses 

 the character of these variations. To a certain extent new permanently 

 varying types may be produced by cultivation in the presence of such 

 reagents. 



Bacillus Urese.* — A. Viehoever has carried out an extensive 

 research upon the properties of the group of organisms, which have the 

 power of decomposing urea, which are associated with the ammoniacal 

 changes that occur in standing urine. The types investigated included 

 Urobacillus pasteurii Miguel, Urobacillus leubii Beijerinck, Bacillus 

 pasteuri Migula, Bacillus probatus A.M. et Viehoever, isolated by the 

 author of this paper, and B. Freiulenreichii Migula. Methods of cul- 

 ture, vegetative properties, morphology, biophysical and biochemical 

 reactions, are discussed in great detail. The powers of resistance to 

 certain toxic substances are investigated, and quantitative determina- 

 tions of the urea-destroying power of known quantities of bacteria are 

 carried out. As regards B. probatus, it would seem that this species 

 might be regarded as one of the nitrite bacteria, possessing the property 

 of converting ammonia into nitrite. It is capable of growth in a 

 nitroo-en-free medium to which has been added ammonium carbonate. 



'to v 



Flora of Pasture and Milk.j — A. AVolff has studied the relation 

 between the bacterial flora of the pasture and of the milk of grazing 

 animals. It was found that, as regards the commoner bacterial types, a 

 very close relationship exists ; such types as Bacillus trifoUi, B. herbi- 

 cola, B. lactorubefaciens being recovered from both sources. This cir- 

 cumstance is probably due to primitive methods of milking the animals 

 and to the use of the hay and straw as litter in the stables. 



Keratomycosis Mucorina.J — V. Oavara gives an account of a case 

 of corneal infection with a mould belonging to the genus Mucor, but 

 which, as far as concerns its pathogenic properties, does not correspond 

 with any species hitherto described. It has received the name of Mucor 

 cornealis. The author refers shortly to records of pathological conditions 

 due to moulds, and conies to the conclusion that this is the first case of 

 corneal infection with organisms of this genus. There are well-marked 

 differences between this infection and keratomycosis aspergillina. The 

 author considers in detail the morphological, cultural and pathogenic 

 properties of M. cornealis as well as the clinical and pathological features 

 of the disease. 



* Centralbl. Bakt., 2te Abt., xxxix. (1913) pp. 209-359. 



t Centralbl. Bakt., 2te Abt. Orig., xxxix. (1914) pp. 411-19. 



% Centralbl. Bakt., lte Abt. Orig., lxxii. (1913) pp. 23-37. 



