Fungous Flora of the Soil 417 



with respect to taking the samples are not given, except the statement 

 that the greatest precaution in all the work was constantly observed. The 

 methods observed in sterilization of media, glassware, etc., were similar 

 to those of Hueppe ('85), whom he followed closely. 



Following Adametz we find Reinitzer, Nikitinsky, and van Iterson 

 interested in the soil flora principally from the same standpoint, the 

 isolation of species with a view to the study of the biochemical processes 

 taking place in the soil. Reinitzer and Nikitinsky were primarily 

 interested in the decomposition of humin substances by soil organisms, 

 while van Iterson busied himself only with decomposition of cellulose. 



Reinitzer ('00) extracted humin substances from garden, wood, meadow, 

 and heath soils as well as from wood mold. The substances after extraction 

 were never sterilized and were allowed to stand in dishes unprotected 

 from the air. No fungous growth took place. Later these substances 

 were inoculated with a sm.all portion of wood soil containing hyph^e, but 

 with only negative results. While valuable data of a biochemical nature 

 resulted from his work, still as to isolation of soil fungi nothing new can 

 be accredited to him. 



Later Nikitinsky ('02) was somewhat more successful in the isolation 

 of soil forms than was Reinitzer. He isolated some thirty forms of bacteria 

 and three species of fungi. While his technic allows considerable room 

 for contaminations, he undoubtedly isolated from the soil the forms men- 

 tioned by him, as they have been isolated repeatedly by other investi- 

 gators since. For his isolation work he used three solutions as follows : 



Solution I Solution II Solution III 



1.5 per cent humic acid i per cent humic acid 1.5 per cent humicacid 



0.5 per cent (NH4)2S04 



— 0.2 per cent cane sugar 



0.2 per cent KH2PO4 0.2 per cent KH2PO4 0.2 per cent KH2PO4 

 0.2 per cent MgS04 0.2 per cent MgS04 0.2 per cent MgS04 



These solutions were placed in ij-liter flasks, plugged, and sterilized 

 in an autoclave at 120° C. for thirty minutes. After cooling they were 

 inoculated with soil extract. The soil extract was obtained from garden 

 soil as well as from the upper and lower layers of forest and humous soils. 

 The humic acid used in the solutions was obtained from the two soils 

 last mentioned. 



('85) Hueppe. Die Methoden der Bakterienforschung. Wiesbaden. 1885. 



('00) Reinitzer, F. Uber die Eignung der Huminsubstanzen zur Ernahrung von 

 Pilzen. Bot. Ztg. 58: .59-73- 1900. 



('02) Nikitinsky, J. Uber die Zersetzung der Huminsaure durch physikalisch- 

 chemische Agentien und durch Mikroorganismen. Jahrb. Wiss. Bot. 37: 365-420. 

 fig. 4. 1902. 



