ASYMMETRICA-VELUTINA 371 



light sporing, produce little or no exudate upon most substrata, and show 

 colony reverse uncolored or in pale yellow shades. This substrain was 

 employed almost universally for the production of penicillin b}^ the surface 

 culture process (Coghill, 1944). 



NRRL 827, cited above, is marked by rapidly growing, comparatively 

 deep, loose-textured, dull blue-green colonies which may develop abundant 

 pale exudate and usually show only a limited yellow pigmentation in re- 

 verse. Strains showing this cultural pattern are regularly poor penicillin 

 producers. 



PenicilUum griseo-roseum Dierckx (Soc. Scien. Brux. 25: 89. 1901. In Biourge, 

 Monogr., La Cellule 33: fasc. 1, pp. 168-170; Col. PI. IV and PI. VI, fig. 31. 1923; 

 Thorn, The Penicillia, pp. 263-264. 1930) as described by Biourge, and as represented 

 by his type strain (reported by Thorn in 1930 as No. 4733.70, now maintained as NRRL 

 820), apparently represents a comparatively deep-growing, loose-textured culture 

 differing little from certain variants known to have developed from well known cul- 

 tures of P. notaUim Westling. Biourge reported overgrowths of rosy mycelium in 

 age, a development which is not infrequently seen in some substrains of Fleming's 

 P. notatuvi, and even more strikingly in certain variants of NRRL 832. A culture 

 from the Centraalbureau in February 1946 as P . griseo-roseum Dierckx (from Biourge 

 in 1929, and possibly derived from the type also) differs from typical strains of P. no- 

 tatiim only in producing deeper, looser-textured colonies with conidial areas in dull 

 blue-green shades and exudate colorless or nearly so. We believe the species should 

 be regarded as synonymous with P. notatum Westling. Strains possessing the cul- 

 tural characteristics of NRRL 820 and the strain from Baarn regularly produce low 

 yields of penicillin. 



PenicilUum cyaneo-fulvum Biourge, in Monograph, La Cellule 33: fasc. 1, 



pp. 174-176; Col. PI. IV and PI. VI, fig. 34. 1923; also Thom, 



The Penicillia, p. 267. 1930. 



Colonies on Czapek's solution agar growing fairly rapidly or somewhat 

 restrictedly depending upon the strain, from 2.5 to 4.0 cm. in 10 to 12 days 

 at room temperature, consisting of a loose-textured often more or less floc- 

 cose felt (fig. 96C) commonly 1 to 2 mm. deep, strongly furrowed in a radial 

 pattern but with central area usually irregularly buckled and wrinkled, 

 with growing margin abrupt, somewhat lobed, white, 1-2 mm. wide, usually 

 light sporing throughout, in light yellow-green shade from gnaphalium 

 green to celandine green, less commonly mineral gray (Ridgway, PI. 

 XLVII); exudate generally abundant, clear and ranging from almost un- 

 colored in some strains to definitely yellow in others; odor lacking; reverse 

 variable, in dull yellow to yellow-brown shades; conidiophores variable in 

 length, arising from the substratum, or less commonly as branches from 

 aerial hyphae, ranging from comparatively short up to 600 to 800^ or more 

 in length by 2.8 to 3.5/x, with walls smooth and colorless; penicilli biverti- 

 cillate and asymmetrical, irregular in pattern, often loosely branched; bear- 



