Charles B. Lipman 173 



Gains of nitrogen were also noted by Heinze 1 in cultures of yeasts 

 in their spore forming stages and in cultures of lichens in the 

 gonidium form. There should also be mentioned here the experi- 

 ments of Gerlach and Vogel 2 in which they found a mold to pos- 

 sess the power of increasing the nitrogen content of the culture 

 from 2.8 mg. to 5.1 mg. This increase is attributed by Gerlach 

 and Vogel to experimental error, but, as Lohnis well remarks in 

 reviewing this matter, the other data given in the same investi- 

 gations do not support such a view. 



In a series of very carefully conducted experiments in which 

 every possible precaution was taken to prevent absorption of 

 ammonia and amido compounds from the air by the culture solu- 

 tions, Frohlich 3 showed very considerable and definite gains of 

 nitrogen in cultures of fungi obtained from their growths on dead 

 parts of plants. These fungi belonged to the hyphomycetes, 

 and one of them Macrosporium commune fixed on the average 

 as much as 8.92 mg. of nitrogen per gram of dextrose used. In 

 addition to these results the same investigator confirmed the results 

 of others above noted with respect to the nitrogen fixing powers 

 of Penicillium glaucum and Aspergillus niger. Latham 4 further 

 confirms the results of Berthelot, Puriewitsch, Saida, Remy, 

 Ternetz, Frohlich and others above mentioned, in his experiments 

 with Aspergillus niger. 



Of particular interest in connection with the writer's results 

 are those of Zikes 5 who describes a torula form, isolated from laurel 

 leaves and named by him Torula wiesneri which possesses a 

 power of nitrogen fixation equal to 2.3 to 2.4 mg. per gram of glu- 

 cose used. The experiments of Lohnis and Pillai 6 show only 

 a slight nitrogen fixing power for a torula form employed by them, 

 but a larger fixation of nitrogen by Dematium pullulans. 



l Centralbl. f. Bakt., x, 2 Abt., p. 675; xii, p. 357. 

 *Beitr. z. chem. Physiol. u. Path., ii, 1907. 

 *Jahrb. f. wissen. Botanik, xlv, p. 256, 1907. 

 4 Bull. Torrey Bot. Club, xxxvi, p. 235, 1909. 

 *Sitzungsber. Akad. Wien, math-naturw . KL, cxviii, p. 1091. 

 8 Lohnis and Pillai: Centralbl. f. Bakt., xx, 2 Abt., p. 799. 



