200 A MANUAL OF THE PENICILLIA 



heavier sporing but in the same tints as on Czapek; exudate hmited; odor 

 not pronounced; penicilH as described above but with conidial chains 

 longer, often exceeding 100/x. 



Colonies on malt agar 3.0 to 4.0 cm. in 10 days, plane, appearing velvety 

 commonly tufted in central colony areas (fig. 54C), in mixed red (from 

 heavily encrusted vegetative hyphae) and blue-green (from conidial struc- 

 tures) shades, with the former predominating in some strains, the latter 

 in others; exudate limited; odor not pronounced; reverse in bright orange- 

 red shades near grenadine red or flame scarlet (R., PI. II); conidiophores 

 arising almost entirely from the substratum, bearing penicilli as described 

 above but with conidial chains up to 150m in length. 



Species description centered upon NRRL 2058 received in May 1946, 

 from Professor Weston, Harvard University, as a strain isolated from ex- 

 posed textiles in Florida. Represented also by NRRL 2059 received in 

 April 1944, from Laura A. Kolk, Brooklyn College, Brooklyn, New York, 

 as a highly pigmented culture from a dilution plate of a water sample taken 

 from a small pond. Also represented by NRRL 2060, received in May 

 1945 from Dr. Lawrence White, Philadelphia Quartermaster Depot, as a 

 strain isolated in Florida from exposed cellulose-nitrate covered cello- 

 phane. When first received, this latter strain was diagnosed as Penicil- 

 lium implicatum Biourge var. aureo-niarginatum Thom. More careful 

 examination of the strain indicates its proper placement to be with P. 

 multicolor G.-M. and P. 



Penicillimn multicolor was isolated originally from Russian soil and was 

 successfully cultivated upon a variety of substrata including potato, 

 carrot, and beet. It did not coagulate milk, thrived in media containing 

 2 to 3 percent lactic acid, but grew poorly in alkaline media. It was 

 characterized particularly by its pigmentation which varied with the sub- 

 stratum and ranged from yellow-orange to dark red, with pigment "grains" 

 often appearing in the large hyphae. The penicilli were monoverticillate 

 and usually unbranched. 



Attempts to obtain the type culture failed. An organism bearing this 

 name received from the authors was found to be replaced by another mold, 

 or to have lost the characteristic features which distinguished it when first 

 isolated. A form believed to approximate the type was subsequently sent 

 to Thom by Professor Waksman as an isolate from New Jersey soil, but 

 this was quickly lost from the collection. Another strain discussed by 

 Thom in his Monograph (1930, p. 213) and in the laboratory was referred 

 to as the "paint" organism, but under continued artificial cultivation lost 

 its pigment producing power. Other strains suggestive of the Penicillium 

 multicolor description were isolated from American sources but failed to 

 survive for long periods in culture. Cultures of this type are apparently 



