ASYMMETRICA-DIVARICATA 315 



in Fehling's solution containing 1.G4 percent copper and to tolerate, with 

 some distortions of the hyphae, concentrations of CUSO4 up to a saturated 

 solution. ^Vlycelia, when ashed, were found to contain up to 1600 p. p.m. 

 of Cu, the amount increasing with that in the medium in lower but not 

 in higher concentrations. Other copper salts, including CuCl and 

 Cu(No3)2 • 3H2O, were somewhat more toxic. Subsequent to this, Sato (1939) 

 described two Penicillia, P. cuprophilum n. sp. and P. hiforme var. vitrio- 

 lum n. var., isolated from solutions containing high concentrations of H2SO4 

 and CUSO4 respectively. The former was reported to grow in a 19 percent 

 solution of CUSO4 whereas the latter would tolerate 21 percent CUSO4. 

 The cultures were sent to us by Sakaguchi and both proved to be repre- 

 sentative strains of P. ochro-chloron. Additional strains of the same 

 species have been isolated from copper solutions and from fabrics im- 

 pregnated with copper-containing mildewcides by other investigators and 

 submitted to us for identification. 



Chrzaszcz and Tiukow (1929) investigated acid production in species of 

 Penicillium now assigned to the P. janthinellum series. 



Kunitz (1938) reported the production of a powerful kinase, changing 

 trypsinogen to trypsin by an unidentified strain of Penicillium. When 

 subsequently studied by Thom the culture proved to be Penicillium jan- 

 thinellum or some closely related form. 



Penicillium canescens Series 

 Outstanding Characters 



Colonies growing somewhat restrictedly upon most substrata, consisting 

 of a fairly compact basal felt with surface growth loose-textured to more 

 or less floccose, conidial areas in light yellow-green to gray-green shades, 

 reverse variable, from dull peach to orange-brown or orange-red de- 

 pending upon the species. 



Conidiophores variable in origin and dimensions, arising either from the 

 substratum up to 400-500^ in length, and bearing metulae irregularly 

 disposed or in fairly well defined terminal verticils; or borne as short 

 branches from aerial hyphae, generally much shorter, and bearing smaller 

 and more irregular penicilli. 



Penicilli conspicuously divaricate, with conidial chains typically adherent 

 in loose divergeng columns. 



Conidia globose to subglobose, with walls variable from smooth in some 

 forms to definitely roughened in others. 



Series Key 



2'. Conidial chains tending to form columns, at least in young cultures; conidia glo- 

 bose to subglobose, somewhat roughened P- canescens series 



aa. Colony reverse developing deep red or brown shades; penicilli strongly di- 

 varicate, not tending toward ramigenous. 



