ASYMMETRICA-VELUTINA 401 



phores, and reverse in comparatively light yellow to brownish rather than greenish 

 to black shades. Recognition of a separate species is believed unwarranted in view 

 of the strain variation characteristic of the P. roqueforti series. 



Penicillium biourgei Arnaudi (Boll. 1st. Sieroterapico Milanese 6: fasc. 1, pp. 25- 

 27, Pis. 1-2, 1927; also Centbl. f. Bakt. etc. (II) 73: 321-330. 1928), as originally re- 

 ported and described seemed to represent a member of the P. roqueforti series which 

 the describers found to be significant in the ripening of Gorgonzola cheese. A strain 

 received from the Centaalbureau in February 1946 under this name and presumably 

 type, since it came originally from the Institute Sieroterapico in Milan, clearly be- 

 longs with P. roqueforti Thorn, differing only in producing more prominent and lighter 

 sporing radial sectors than most strains. The comparative studies of Arnaudi in- 

 cluded fourteen races of mold found in cheese, all of which apparently belonged to 

 the P. roqueforti series. 



Penicillium casei Staub, in Centbl. f. Bakt. etc. (II) 31: 454-46G, 1911; 

 Thorn, The Penicillia, p. 270. 1930 



Colonies on Czapek's solution agar restricted, 2.0 to 2.5 cm. in diameter 

 in 2 weeks at room temperature, buckled and wrinkled, with marginal area 

 deeph' dissected by 4 or more radial furrows, somewhat zonate, velvety, 

 heavily sporing, growing marginal zone 1.0 to 1.5 mm. wdde, white, shading 

 into fairly bright yellow-green shades from asphodel green through pois 

 green to leaf green (Ridgway, PL XLI); exudate limited, light yellow, 

 mostly in central colony areas; odor very faint or lacking; reverse in yellow 

 to orange, brown, or almost black shades, with the color somewhat diffused 

 into the surrounding agar; conidiophores borne in a dense stand, arising 

 mainly from a closely interwoven and tough basal mycelial felt, mostly 150 

 to 200m in length by 3.0 to 4.0m, but ranging from 100 to 250m, with walls 

 usually conspicuously roughened; penicilli asymmetric, irregularly 

 branched, with spore bearing apparatus variable in length from 20 to 60m 

 but mostly 40 to 50m, typically consisting of one or more branches in addi- 

 tion to the main stem, each terminating in a cluster of metulae bearing 

 sterigmata and spore chains at first adhering into poorly defined columns 

 but later appearing as an irregular tangled mass up to 50m or more in length; 

 branches variable in size, mostly 12 to 20m by 3.0 to 4.0m, occasionally re- 

 branched; metulae borne in groups of 3 to 5, mostly 7.0 to 12.0m by 2.5 to 

 3.5m; sterigmata in small clusters, mostly 7.0 to 9.0m by 2.2 to 2.7m with 

 longer individuals occasionally borne at the level of the metulae; conidia 

 subglobose to broadly elliptical, 3.0 to 3.5m in long axis, smooth-walled, 

 yellow-green en masse. 



Colonies on steep agar growing more rapidly, attaining a diameter of 3.0 

 to 3.5 cm. in 2 weeks at room temperature, closely and conspicuously fur- 

 rowed in a radial pattern, heavily sporing, in color and general texture 

 duplicating colonies on Czapek agar; penicilli generally somewhat larger 



