284 a manual of the penicillia 



Penicillium lilacinum Series 

 Outstanding Characters 



Colonies typicall}' loose-textured to floccose, growing rapidly, light to 

 heavy sporing, in lilac to light vinaceous or avellaneous — ^never in green 

 — shades. 



Conidiophores varying greatl}' in length, arising from the substratum or 

 as branches from ascending hyphae, with walls smooth or finely rough- 

 ened. 



Penicilli conspicuousl}^ divaricate, of variable dimensions, commonly con- 

 sisting of terminal clusters of divergent metulae, or appearing as mono- 

 verticillate structures when borne on short branches from ascending 

 conidiophores. 



Sterigmata acuminate with spore-bearing tubes, typically long, thin, and 

 pointed. 



Conidia usually elliptical to lemon-shaped, commonly appearing apiculate, 

 smooth-walled. 



Series Key 



A. Colonies not showing green, gray-green or blue-green with the ripening of conidia. 



1. Colonies deeply floccose, becoming lilac, vinaceous or violaceous with the de- 



velopment of conidia P. lilacinum series 



a. Colonies developing lilacinus (Saccardo) or vinaceous (Ridgway) shades, 



with reverse similarly colored, or in some strains becoming purple-red. 



P. lilacinum Thom 



b. Colonies developing violet shades near "light lobelia violet" (Ridgway) 



with ripening of conidia and with reverse in bright yellow shades. 



Spicaria violacea Abbott 



2. Colonies not deeply floccose, comparatively thin, often strongly wrinkled, 



becoming pinkish-buff to avellaneous with ripening of conidia. 



P. humiili van Beyma 



3. Colonies velvety or nearly so, with conidial areas in tan, cream, or near-white 



shades, never showing green Natural mutants of many species. 



Strictly speaking, this series includes the single and rather easily recog- 

 nizable species, Penicillium lilacinum Thom. Two additional species are 

 considered with it as a matter of convenience. In these a degree of true 

 relationship is suggested, but this remains to be established. The first 

 of these, P. humuli v. Beyma, produces conidia in pale pinkish buff shades 

 and normally shows penicilli that are strongly divaricate, usually con- 

 sisting of a single verticil of 2 or 3 terminal metulae. Sterigmata are not 

 as a rule conspicuously tapered or pointed, and mature conidia are nor- 

 mally subglobose to globose rather than elliptical. 



The second species, Spicaria violacea Abbott, in its typical form, is 

 clearly separable from Penicillium lilacinum. However, strains appar- 



