660 SUMMARY OF CURRENT RESEARCHES RELATING TO 



culture. Good results were obtained by growing it on gypsum plates, 

 either in Petri's dishes, or in test-tubes along with the above mannite 

 solution. It grows best at about 80° C. The author has found it in 

 garden and field earths from various parts and also in street dust. It 

 was constant in earth at a depth of 50 cm. At depths of 100-100 cm. 

 it did not seem to be present, although Clostridium pastorianum was. 

 Its most interesting characteristic is that it absorbs atmospheric N, 

 even in pure cultures. In a series of experiments, after nine weeks 

 growing in the mannite solution, the N-gain was found to be 12-24 mg. 

 per litre. In mixed cultures the growth is much more luxuriant and 

 the N-gain greater, up to 80 mg. per litre, after one week. The greatest 

 N-gain seemed to be in the gypsum cultures, they being under very 

 aerobic conditions. They furnished, in periods varying from one to 

 three weeks, about 4 mg. N each, and as the quantity of the nutrient 

 solution, used in each, was about 20 c.cm. the amount of N per litre 

 would be about 160 mg. 



Attempts to sow earth with cultures of these organisms for the 

 purpose of increasing its nitrogenous value have not hitherto been 

 satisfactory. 



Disease of the Rat caused by an Acid-fast Bacillus.* — G. Dean 

 records a case of a disease of the rat (Mus decumanus) affecting skin, 

 musculature and glands, a disease already described by Stephansky and 

 by Rabinowitsch. Among other lesions, the skin of thorax and 

 abdomen was denuded of hair, and on the bare area were several nodules 

 the size of peas. The axillary "glands were enlarged, and the abdominal 

 wall was thickened and caseous. Practically the whole area involved 

 was packed with acid-fast bacilli. They were present not only in 

 necrotic areas, but in the cells themselves. The bacilli are about 5 /a in 

 length, and frequently present the granular appearance of the bacillus of 

 leprosy. They stain with Gram and are both acid- and alcohol-fast. 

 Attempts to cultivate the bacillus on ordinary media failed, as also did 

 attempts to infect white rats. 



Acid-fast Bacilli in Python reticularis.! — V. Hausemann found, in 

 the neighbourhood of the pancreas in a Python reticidaris, a grape-like 

 mass having some resemblance to Perlsucht. Microscopically, however, 

 the masses were seen to consist of granulation tissue, with densely 

 packed round cells, but with no caseation, giant cells, nor calcification. 

 Foci of suppuration were seen, in the neighbourhood of which were large 

 cells with characteristic granular protoplasm. With the usual staining 

 method no bacteria were seen. With the use of Ziehl's solution and 

 after treatment with Gabbet's solution, numerous red-stained rods 

 appeared, resembling the tubercle bacillus in form and size, and some- 

 times having the irregular staining so frequent in that organism. By 

 this staining method the granular appearance of the large cells was seen 

 to be due to an accumulation of acid-fast bacilli in them. These large 

 cells with their contained bacteria appeared morphologically equivalent 

 to " lepra-cells." As all the material had been hardened before the 



* Centralbl. Bakt., 1* Abt., xxxiv. (1903) pp. 222-4. 

 t Tom. cit., pp. 212-3. 



