370 



SCIENCE. 



[N. S. Vol. XVII. No. 427. 



with hen's, rabbit's and guinea-pig's sera 

 was unsuccessful. The animals immunized 

 with dog's haemoglobin possessed, after re- 

 peated injections, a serum not differing 

 from the normal, while the animals treated 

 with hen's haemoglobin developed agglu- 

 tinins and lysins present in dilutions of 

 1-100 parts. 

 On the Nature of 'Pyocyaiwlysin': E. 0. 



Jordan, University of Chicago. 



A number of bacteria, including patho- 

 genic forms like the tetanus bacillus, and 

 ordinary saprophytes like B. megatherium, 

 have been reported as producing haamo- 

 lysins in their broth cultures. B. pyocy- 

 aneus is one of these forms, and 'pyocy- 

 anolysin' has been generally considered as 

 belonging in the same general category 

 with tetanolysin and staphylolysin. 



The well-known laking effect of alkalies 

 and the fact that old cultures of B. pyocy- 

 aneus possess a strongly alkaline reaction 

 led to inquiry into the relation between the 

 alkalinity of the bacterial filtrate and the 

 power of the filtrate to produce haemolysis. 

 It was found that the filtrates from broth 

 cultures of B. pyocyatieus (seven strains, 

 one freshly isolated and quite virulent) 

 produced no greater hEsmolysis than NaCl 

 solution, or sterile broth of the same de- 

 gree of alkalinity. The alkalinity of B. 

 pyocyaneus filtrate sometimes reaches as 

 high as 2.6 per cent, normal alkali. If 

 the alkalinity of the B. pyocyaneus filtrate 

 be increased or diminished, the heemolyzing 

 power is correspondingly affected. The 

 heemolytic power is practically destroyed 

 by neutralization (indicator, phenolphtha- 

 lein). Most bacterial hsemolysins, like the 

 hemolysins of blood sera, are inactivated 

 by exposure to a temperature of 56° ; but 

 'pyoeyanolysin' will withstand 125° for 

 at least an hour. The statements regard- 

 ing 'pyoeyanolysin' made by Bullock and 

 Hunter, Weingeroff, Breymann and Loew 



indicate that the haemolyzing power ob- 

 served by these writers in the filtrate of 



B. pyocyaneus is no greater than might be 

 due to the simple alkalinity of the medium. 

 It is possible that other strains of B. pyocy- 

 aneus may be found which produce some 

 other hsemolysin than alkali, but it is evi- 

 dent that in any study of bacterial hsemoly- 

 sins the superimposition of the effect of 

 alkali upon that of any other haemolyzing 

 substance must be reckoned with, espe- 

 cially when corpuscles so sensitive to alkali 

 as those of the dog are used for test objects. 



A Fat-splitting Torula Yeast Isolated from 

 Canned Butter: L. A. Rogers, Biochemic 

 Laboratory, Washington, D. C. 

 The author has isolated from several 

 samples of canned butter, a torula yeast, 

 possessing to a limited degree, the ability 

 to split up glycerides with the liberation of 

 free fatty acid. The action of this torula 

 is much weaker than that of the fat-split- 

 ting molds. 



The acid number of a pure butter fat 

 inoculated with a milk culture of the 

 torula, increased in two weeks from 0.579 

 to 3.474. 



The cells are elliptical, about 3.5 ,j, long 

 and have little tendency to form chains or 

 bunches. 



The yeast ferments maltose slowly at 37° 



C, but does not ferment lactose, galactose, 

 levulose, mannose or cane sugar. 



A complete description will be given in 

 a later paper. 



Oligonitrophilic Bacteria of the Soil: 

 Frederick D. Chester, Delaware Agri- 

 cultural Experiment Station. 

 Reference is given to the early literature 

 bearing upon the subject of nitrogen as- 

 similation by lichens, aerophilous algae, 

 molds and bacteria. 



Land may gain in nitrogen through the 

 activities of soil bacteria. Oligonitrophilic 



