558 Bulletin 167 



peared in 24 hours, as a faint white streak, rapidly becoming 

 beaded above, moist, glistening and of slimy consistency. It 

 had a white to light grayish color and often appeared nacreous 

 in certain lights. The medium became more or less green 

 fluorescent on the third day, the coloration gradually increas- 

 ing in intensity. Strain CXV grew more slowly than the others 

 and with doubtful fluorescence. 



2. Potato slants. — Cylinders were cut from large tubers 

 and divided so as to give a slant surface. These were washed 

 for several hours in flowing tap water before they were placed 

 in the tubes containing a few drops of distilled water. Sterili- 

 zation was accomplished by the intermittent method. 



Upon this medium a moderate growth occurred with all 

 strains. At first in about twenty-four hours a very delicate 

 whitish accumulation could just be distinguished. This de- 

 veloped slowly into a light brown, slimy, smooth, filiform, 

 spreading band, later becoming thick and darker brown, some- 

 times even chocolate brown in old cultures. Strain CXV was 

 characterized frequently by a more or less corrugated to rhizoid, 

 slimy growth, moist at first, later appearing rather dry. The 

 medium was more or less grayed by all strains. Strong green- 

 ing of the substratum was present with some strains but not 

 constantly. This reaction was observed with the following 

 strains; CXII, in 31 days: CXLV, CXLVIII, LI in 5 days; 

 Ps. fluorescais in 3 days. 



3. Loeftlcr's blood scrum. — This medium was not em- 

 ployed. 



4. Agar stab. — Specific differential characters were not 

 found on this medium. The surface growth was moderate 

 with all 13 strains, at first white, becoming more or less brown, 

 round and entire to contoured with toothed edge. The punc- 

 ture growth which was at first beaded to filiform became echin- 

 ate to villous, the latter character being typical of old cultures. 

 The best development occurred in the upper portion of the stab. 

 The medium was at first blue-green fluorescent, becoming more 



