932 



SCHIZOMYCETES 



which Chalmers and O'Farrell in 1913 named and more fully de- 

 scribed. It is found in Trichomycosis rubra, and we differentiate the 

 three species as follows: — 



A. Does not ferment glucose — Castellanii. 



B. Produces slight acidity in glucose: — 



I. Nitrates reduced to nitrites — Rosens. 

 II. Nitrates not reduced — Fulvus. 



Genus Nigrococcus Castellani and Chalmers, 1918. 



Definition. — Micrococcese saprophytic, rarely parasitic, produc- 

 ing black or bluish-black pigment. 



Type. — Nigrococcus nigrescens (Castellani, 191 1). 



Classification. — The type is found in Trichomycosis nigra, along 

 with Cohnistreptothrix tenuis Castellani; other forms are N. fuscus 

 Adametz (1888), in water; A^. cyaneus Schroeter, 1870, in air 

 and water; and they may be differentiated as follows: — 



A. Gelatine liquefied — Fuscus. 



B. Gelatine not liquefied: — 



I. Pigment indigo blue — Cyaneus. 

 II. Pigment black — Nigrescens. 



iNCERTiE SeDIS. 



The so-called Micrococcus melitensis Bruce, 1886, which is the 

 causal agent in Mediterranean, Malta, or undulant fever, is difficult 

 to classify, because elongated forms are seen at times in cultures, 

 and because it seems to have no affinity with the Gram-negative 

 cocci; but, on the other hand, is very like the typhoid-colon group of 

 organisms in certain respects. It does not ferment sugars, nor 

 produce indol; does not liquefy gelatine, nor show polar-staining; 

 while milk becomes alkaline. 



FAMILY BACILLACEiE Fischer, 1894. 



Definition. — -Eubacteriales with cells long or short, flagellate or 

 non- flagellate, sporogenous or non sporogenous, but always cylin- 

 drical and straight. They divide in one direction only. 



Type Qf^mxs —Bacillus Cohn, 1872. 



Remarks. — -The enormous numbers of species and varieties 

 gathered together under the names Bacterium and Bacillus form 

 such an unwieldy mass, that we have endeavoured to simplify 

 matters by formulating a number of tribes with genera. 



Classification. — -The family ' Bacillacese ' may be classified into 

 tribes as follows :— 



Growth in ordinary laboratory media : — 



A. Entirely or almost entirely absent — Tribe i, Nitrohacterecs. 



B. Poor, Gram-negative, grow best on blood media^ — -Tribe 2, Hamo- 



philecs. 



C. Extremely slow and scanty growth on ordinary and blood media — 



Tribe 3, Gvaciloideee . 



D. Growth good: — 



I. Endospores present — Tribe 4, Bacillea. 



II. Endospores absent: — 



