ASYMMETRICA-DIVARICATA 275 



penicilli produced in the two series are sufficiently similar to warrant 

 placing them in juxtaposition in a system of classification based primarily 

 upon the pattern of conidial structures. Furthermore, the true sclerotia 

 developed in Pemcilliimi raistnckn of this series strikingly resemble the 

 sclerotioid, late-ripening pe^rithecia seen in P. asperum and P. baamense 

 in the Carpenteles series, and seem to differ from the latter principally in 

 the fact that they consistently fail to develop an ascogenous stage. 



Penicillium raistnckn Smith, in Trans. Brit. Myc. Soc. 18: 90, PL IV, 



fig. 4, PI. V, figs. 5 and 6. 1933. 



Smith's diagnosis as follows: 



"Colonics growing rapidly on most media at temperatures up to 30°C., rate of 

 growth much less above 30°C. and nil at 37°C.; bluish green, then greyish green, and 

 finally somewhat brown, velvety; reverse persistently uncoloured, showing masses 

 of sclerotia; conidiophores arising from the substratum, up to 250m long, 3.5 to 4.0m 

 in diameter, rough; penicilli typically divaricate, comprising 3 to 5 monoverticillate 

 heads united into a fairly compact whole; metulae clavate, sometimes very slightly 

 roughened, 10 to 13m by 4.0 to 4.8m; sterigmata closely packed on each individual 

 metula, 7.5 to 9.0m by 2.6 to 3.0m; conidia globose or nearly so, smooth, 2.2 to 2.7m in 

 diameter, conidial chains packed into diverging solid columns; sclerotia produced 

 abundantly, hard, feeling like grit under a cover-glass, consisting of masses of irregu- 

 lar-shaped thick-walled cells, white to dirty white, globose or ovoid, up to 180m in 

 long axis. 



"This species is noteworthy chiefly on account of its very free production of scle- 

 rotia." 



Our notes follow: 



Colonies on Czapek's solution agar about 3.0 cm. in 12 to 14 days at 

 room temperature, velvety, usually producing abundant conidial struc- 

 tures arising primarily from the substratum, in blue-green shades near 

 dark glaucous gray (Ridgway, PI. XLVII), azonate or slightly zonate, 

 lightly furrowed in a predominantly radial pattern (fig. 73 A), showing 

 some tendency toward sector variation, developing limited areas ahnost 

 floccose and bearing conidial structures from aerial hyphae; limited clear 

 exudate produced; odor lacking; reverse uncolored to vinaceous drab 

 shades; details of the penicillus as described by Smith except conidia com- 

 monly appear elliptical and range up to 3.0 to 3.3m in diameter; developing 

 abundant sclerotia (fig. 73C) throughout the entire colony (see above) 

 and often characterizing its appearance. 



Colonies on steep agar growing more rapidly, 4.0 to 4.5 cm. in 12 to 14 

 days, in color and texture as on Czapek but with reverse in orange-brown 

 shades and surrounding agar uncolored. 



Colonies on malt agar spreading, about 4.5 cm. in two weeks (fig. 73B), 

 plane, often showing a marked tendency to sector, with some areas heavy- 



