304 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



fV0L. 10 



when amino acids were supplied as the sole N source. Amino 

 acids, moreover, as the sole source of both C and N had very 

 little value for these forms. 



Kossowicz ('12), in his cultural studies with 10 fungi, including 

 a Botrytis, several species of Penicillium, a Phytophthora, and 2 

 species of Aspergillus, found that KNO, formed a good N source 

 in the presence of cane sugar or dextrose. All these forms like- 

 wise made good growth with urea or uric acid as the N source. 

 The following exceptional things were noted. With cane sugar 

 as the C source Cladosporium herbarum would grow neither on 

 glycine nor hippuric acid, and Penicillium crustaceum , P. brevi- 

 caule, and Aspergillus glaucus also failed to grow on the latter 

 acid. All 4 of these fungi, however, grew on both acids in the 

 presence of dextrose or mannite. For a number of the fungi 

 glycine, uric and hippuric acids were found to serve to a small 

 extent as sources of both C and N. Extracts of several of the 

 fungi each fermented uric and hippuric acids, showing that the 

 process is enzymatic. His 1914 contributions may be summed 

 up as follows. Using the same 10 fungi, he found urea, uric 

 acid, hippuric acid, glycine, guanine, guanidine compounds, 

 nitrites, nitrates, and CaCN a serviceable as N sources in the 

 presence of cane sugar, the CaCN,, however, only weakly. Uric 

 acid, hippuric acid, glycine, and guanine in the presence of a 

 mixture of mineral N sources (KNO„ NHJ\ T 0„ and NH<C1) 



served as C sources, but urea, guanidine, and KSCN failed to do 

 so. 



Growing the fungi on a KNO,-sucrose medium and at intervals 

 testing for nitrites, Kossowicz obtained positive indications in all 

 cases but very irregularly. Ammonia formation was evident in 

 cultures of Aspergillus niger and A. glaucus, Cladosporium 

 herbarum, Penicillium glaucum, and Fusarium sp., but the fact 



that he did not obtain NH, in 21 days' incubation, as shown by 

 his seventh experiment, indicates autolysis as the cause for its 

 presence. Distillation with MgO was used for NH, determi- 

 nation, 20 ml. of the culture solution being taken; the Greiscz and 

 the Zn-iodide-starch methods were employed for the qualitative 

 nitrite test and Nessler's reagent for NH,. Of 7 different yeasts 

 tried the formation of nitrite from nitrate could not be established 

 for any. Nitrate was found a poor source of N for veasts. 



