ASYMMETRICA-DIVARICATA 307 



often difficult to establish, variable in size from 10 to 20m by 2.0 to 2.5m 

 with walls commonly rough; sterigmata borne in groups of 3 to 10, usually 

 compactly arranged but with apices divergent, about 7.5 to 8.5 by 2.0^, 

 with basal portion about G.O/i in length, then narrowed abruptly to form a 

 slender conidium-bearing tube, 1m or less in diameter; conidia elliptical, 

 with one end commonly apiculate, mostly 3.0 to 3.5m by 2.0 to 2.5m, with 

 walls smooth or very delicately roughened. 



Colonies on steep agar spreading broadly, 7.0 to 7.5 cm. in 12 to2,14 

 days at 25°C., in texture essentially as on Czapek but showing a greater 

 diversity of color, with central colony areas predominantly sterile and 

 approxunately tilleul-buff (R., PL XL), ranging to court gray or mineral 

 gray (R., PL XLVII) in submarginal areas where conidial structures are 

 more abundantly produced; exudate limited in amount, colorless to pale 

 straw color; odor lacking or indefinite; reverse in dull, dirty orange shades; 

 penicilli similar in pattern but more abundantly produced and consistently 

 larger than on Czapek, with conidial chains tangled, often more than IOOm 

 in length. 



Colonies on malt extract agar spreading broadly, commonly covering 

 the entire culture plate (9 cm. ±) in 12 to 14 days, in some strains sporu- 

 lating lightly, approximating court gray (R., PL XLVII) and appearing 

 loosely floccose (fig. 82B), 2 to 3 mm. deep, in other strains sporulating 

 abundantly, approximating light pea green (R., PL XLVII), appearing 

 almost velvety to the naked eye but showing a surface network of aerial 

 hyphae and thin ropes of hyphae when examined under low powers; 

 reverse in dull orange shades; no exudate or odor; penicilli essentially as 

 on steep agar but more abundantly produced and with walls more coarsely 

 roughened. 



Species description centered upon NRRL 926 received from Professor 

 Hotson, University of Washington, Seattle, from a two percent solution of 

 copper sulphate. Duplicated also by NRRL 927, received from C. L. 

 Bedford, University of California as a copper sulphate-tolerant mold; 

 NRRL 924 received from Dr. K. Sakaguchi, Tokyo Imperial University 

 as the type strain of PenicilUum cuprophilum Sato, also copper tolerant 

 and capable of growing in high concentrations of copper sulphate and 

 sulphuric acid (this differs from the above in producing more restricted 

 colonies on malt) ; NRRL 925 received from Sakaguchi as P. bifonne var. 

 vitriolum Sato, likewise copper tolerant and capable of growing in high 

 concentrations of sulphuric acid and in solution of copper sulphate up to 

 21 percent (1939), dupHcates almost exactly cultures NRRL 926 and 927. 



The repeated isolation of this species from copper solutions can hardly 

 be regarded as a coincidence. We are led to presume that we are dealing 

 with a form characterized by an unusuil tolerance of this metal. Peni- 



