280 A MANUAL OF THE PENICILLIA 



almost lanose, radiately wrinkled (fig. 75A), at first white, gradually de- 

 veloping conidial structures after one w^eek, thinly scattered throughout 

 but produced more abundantly near the colony margin and particularly 

 adjacent to the intercolony area, in pale gray-green shades near gnaphalium 

 green (Ridgway, PI. XLVII); odor lacking or indefinite; exudate limited to 

 abundant, clear; reverse uncolored to pale peach; with thick- walled, sterile 

 cells in small masses up to 50 to 60m in diameter, suggesting small sclerotia 

 (fig. 75D), occurring adjacent to the substratum throughout the colonies 

 but most abundantly along the intercolony margins, resembling fine white 

 sand in appearance (fig. 7oC) but not firm or gritty; penicilli borne upon 

 long conidiophores with walls finely roughened, up to 1 mm. by about 2.5 

 to S.Ofx, arising from the substratum along intercolony margins and upon 

 branches of variable length arising from aerial hyphae in central colony 

 areas; penicilli variable, in large structures usually consisting of a ter- 

 minal verticil of 3 to 5 metulae (fig. 7oF), 8 to 12^ by 2.5 to 3.0m, enlarging 

 upward, each bearing clusters of 5 to 8 closely crowded sterigmata, not 

 strongly divaricate but with individual metulae having the appearance of 

 monoverticillate penicilli, in smaller structures usually consisting of 2 

 or 3 metulae which may or may not be borne at the same level; sterigmata 

 mostly 6 to Sju by 2.0/x with conidium-bearing tips short, not pronounced; 

 conidia at first elliptical, becoming globose to subglobose at maturity, 

 mostly 2.5 to 3.0ai in diameter, with surface smooth or very delicately 

 roughened. 



Colonies on steep agar 5.0 to 5.5 cm. in 10 to 12 days, approximately 1 

 mm. deep, loose-textured with surface appearing lanose, heavily sporu- 

 lating throughout, gnaphalium green in mature conidial areas (R., PI. 

 XLVII); exudate limited; numerous sclerotia-like masses produced; peni- 

 cilli mostly borne upon long, erect conidiophores and generally larger than 

 on Czapek but of the same basic pattern. 



Colonies on malt extract agar spreading, 6 to 8 cm. in 12 days at 24° C, 

 thin, very loose, floccose, medium sporulating throughout; with small 

 masses of sterile cells abundantly produced adjacent to the substratum 

 (fig. 75B); penicilli as described above; no exudate; reverse in dull brown 

 shades, usually producing a zone of more intense color at the colony margin 

 in age. 



Species description based primarily on NRRL 2023, received in May 

 1946, from the Centraalbureau as Zaleski's type strain. Also represent- 

 ative of the species is a culture received from Baarn as Zaleski's strain, 

 presumably tj^pe, of PeniciUiimi matris-meae. In the latter culture, masses 

 of thick-walled cells were scattered but present; and in cultural aspect it 

 duplicated the preceding, even to the point of producing a marginal brown 

 zone in malt agar plates. This same culture, NRRL 912, as maintained iu 



