BY U. GREIG-SMITH. 33 



became brownish. In Lemco-broth, with various sugars, the 

 bacteria formed surface-rings, but there was no production of 

 acid. 



Bacillus No. ii. {Rhizohuim limosospongiae, n.sp.) formed, oii 

 nutrient agar, a very scanty, slowly growing collectioa of isolated 

 colonies, which slowly fused as a translucent, glistening, raised 

 growth. The cells were entirely of the bacteroid type, as found 

 in the tubercles of certain Leguminosse. The growths in bouillon 

 were scanty, nitrates were reduced to nitrites, and indol was 

 formed. Litmus-milk became alkaline. The bacterium would 

 not grow on gelatin, either glucose or nutrient. On potato, the 

 growth was dull white, flat, and scanty. In Lemco-bouillon con- 

 taining saccharose, dextrose, levulose, lactose, mannit or glycerin, 

 surface-rings were formed, but there was no production of acid. 

 No motility was ever observed. 



While the bacteria are capable of producing slime upon the 

 surface of certain nutritive agar media, they are apparently 

 incapable of doing so when immersed in fluid. This was shown 

 in an experiment in which the bacteria were grown, for three 

 weeks, in a faintly acid solution containing asparagin(0 06 %), 

 sodium pliosphate(0-2 %), and levulose or dextrose(2 %). This 

 nutrient fluid favoured the formation of branched forms of 

 hhizohhim leguminosarum, but did not do so with these two 

 bacteria. In the fluids, which were a centimetre deep, no slime 

 was produced; and a similar absence of slime was noted in the 

 cultures in Lemco-bouillon with various carbonaceous nutrients. 



The condition, as regards the supply of oxygen, will be very 



much the same upon the surface of a damp sponge, as upon the 



surface of agar, while the nutrients are quite difi'erent. The 



question, therefore, arises, from what substance is the slime 



elaborated in the sponge "? The solids of the water will supply 



the necessary saline matter, and it is conceivable that the traces 



of nitrogenous matter derived from the skin may be the source 



of the carbon. It may be the soap, but one does not expect that 



a sodium fatty acid salt would do this. In experiments with 



fluid and solid (agar) uifdia containing asparagin and soap, no 

 3 



L I 8 R A R yX 



