SAPROPHYTIC MICROCOCCI. 213 



active causes of this dehydration, and gave to this 

 organism the name of M. urea; Leube has recently 

 shown that a large number of bacteria (such as sarcinae 

 from the lungs, and several bacilli which are found in 

 ammoniacal urine see under " bacilli") can set up 

 the same decomposition with, to some extent, the same 

 energy. In the author's laboratory another coccus was 

 isolated from decomposing urine, which, like the preced- 

 ing, causes an energetic fermentation of urea, but shows 

 certain differences in the characters of growth ; more 

 especially it liquefies the gelatine. 



Micrococcus urece liquefaciens. 



Spherical cells, 1*25 2 //. in diameter, single or Amicrocpccus 

 forming chains of 3 10 individuals or irregular groups. Hq^fi^the 

 On gelatine plates they form in two days small white gelatine, 

 points, which under a low power appear as dark- 

 grey circular discs, with sharply defined borders. 

 When they reach the surface the colonies become 

 markedly larger; when magnified 80 times they have 

 the appearance of dis^ss of a yellowish-brown colour, 

 which often contain in their middle a dark nucleus 

 the deeper portion of the colony; the surface of the 

 discs is distinctly granular ; the borders gradually 

 assume a wavy character, at the same time gradual 

 liquefaction of the gelatine occurs. In the puncture 

 cultivation a white confluent layer is at first formed along 

 the needle track, then liquefaction of the gelatine soon 

 occurs, and extends to the wall of the glass ; finally, the 

 half or the greater portion of the tube becomes filled with 

 a whitish turbid fluid, at the bottom of which a thick 

 whitish-yellow deposit lies. 



It might appear doubtful which of the two cocci described 

 above was the one referred to in the observations published 

 formerly at a time when a definite isolation of the individual 

 species was not possible. Nevertheless, the circumstance 

 that in Leube's elaborate experiments the organism first 

 described was chiefly met with in the great majority of cases, Biological 

 is in favour of the view that former observers were working properties of 

 with it. From the numerous contributions to the biology 



