250 BOTANICAL GAZETTE [OCTOBER 
With this well established knowledge regarding bacteria, the 
suggestion has been easy that the closely related organisms, the 
fungi, might also be found, at least some of them, to possess a 
similar nitrogen-assimilating power. Acting on this suggestion, a 
number of investigators within the last 15 years have given atten- 
tion to this phase of the problem. 
Inasmuch as this paper is concerned mainly with this question, 
a brief historical survey seems desirable. The oldest work on 
nitrogen-fixation is cited: by FRANK (10), and later by FROELICH 
(11), as having been carried on by JopIN (12) in 1862. A rich 
fungous growth was observed on nitrogen-free media supplied with 
sugar, tartaric acid, or glycerin. The purity of the cultures was 
not certain, although atmospheric nitrogen compounds were 
excluded and analytical methods were used. Later, BERTHELOT 
(13) in 1893 reported nitrogen-fixation for three fungi: Aspergillus 
niger, Alternaria tenuis, and a species of Gymnoascus, cultivated 
on a medium containing CouHn’s (cited by SmiTH 14) solution, to 
which had been added tartaric acid or sugar and kaolin. He claims 
purity of culture only for Alternaria, in which case he reports a 
nitrogen gain as high as 98 per cent of the original nitrogen content. 
During the same year, FRANK (15) also reported nitrogen-fixation in 
certain fungi which he found growing on a nitrogen-free solution of 
sugar and mineral constituents. Later, using Penicillium clado- 
sportoides Fres. (Hormodendron cladosporioides Sacc.) on a similar 
solution, and applying chemical analysis to determine nitrogen 
gain, he found a gain of 3.5 mg. in a 65 cc. culture. 
Further positive results have more recently been reported by 
Purtewitscu (16), Sapa (17), TERNETZ (18), FROELICH (11); 
and LatHam (20). PuRiewirscu, using Aspergillus niger and Pent- 
cillium glaucum, cultivated on nitrogen-free media with tartaric 
acid and varying quantities of cane sugar, secured a nitrogen gain 
of 1.5-8.4 mg. for Aspergillus and 2.0-5.2 mg. for Penicillium. 
Sapa worked with a large number of species, including Phoma 
betae, Mucor stolonifera, Aspergillus niger, Endococcus purpurascens, 
Acrostalagmus cinnabarinus, Monilia variabilis, and Fusispormm 
moschatum. He cultivated these on synthetic media with varying 
quantities of sugar. He also used cultures with and without fixed 


