CLADOTHRIX 515 



CLADOTHEIX DICHOTOMA (Cohn) 



LIQUEFIES GELATINE 



Authority. Cohn. See also'Sur les Caracteres des Cultures du Cladothrix 

 dichotoma, Cohn,' Mace, Comptes rendus, vol. cvi., 1888, p. 1622. 



Where Found. Present in large numbers in both fresh and brackish water, 

 and in both running and stagnant water, especially in the latter when rich in 

 organic material. When it is present in large numbers in water it gives rise to 

 whitish flocculent masses. 



Microscopic Appearance. Long motionless filaments, about 0-4 /* broad 

 and reaching sometimes a millimetre even in length. Distinct branching of 

 the filament is visible. The contents are hyaline. It is straight or sinuous, 

 sometimes undulatory or spiral. The filaments separate up into isolated 

 segments either straight, or comma-, or spiral-shaped, endowed with motility, 

 and with a tendency to unite together to form small flaky zoogloea masses. 



Cultures. 



GELATINE PLATES. Forms in four to five days very small yellowish dots, 

 which are surrounded by a brown halo which extends more and more over the 

 gelatine. On reaching the surface it appears as a small brownish button, some- 

 times having a white efflorescence surrounded by a very brown halo, and a 

 depression due to the slow liquefaction of the gelatine, which it causes. (Mac6.) 



GELATINE TUBES. Forms a thin greyish expansion which slowly liquefies 

 the gelatine. The liquid remains clear, but acquires a brown colour, and a 

 quantity of flocculent material collects at the bottom. (Mace.) 



AGAR-AGAR. Forms at 35 C. a shining thick expansion, which adheres so 

 closely to the agar that it is impossible to remove it without also carrying away 

 portions of the agar. The expansion exhibits a great tendency to form con- 

 centric rings. Sometimes the growth becomes covered with a greyish efflor- 

 escence, which is dry and very brittle. The agar becomes strongly brown in 

 colour. (Mace.) 



BROTH. Forms light whitish flakes with a radiated appearance. The 

 liquid remains clear, but becomes brown in colour. It grows rapidly at 37 C. 

 (Mace.) 



Remarks. All the cultures have a very strong, mouldy smell. 



L L 2 



