20J: A MANUAL OF THE PENICILLIA 



sisting of slender hyphae developing a close-textured felt (aerial and 

 submerged) about 400 to 500^ deep, firm but splitting rather easily, 

 sporulating abundantly in gray-green shades from celandine green to 

 puritan gray or court gray (Ridgway, Pl.XLVII); odor none; exudate not 

 seen; reverse in shades of pale to dark orange-red approaching brick red 

 (R., PI. XIII); conidiophores mostly less than lOO/x by about 2ju, occa- 

 sionally longer, with walls smooth or slightly granular; penicilli strictly 

 monoverticillate, consisting of small verticils of 5 to 8 or 10 parallel sterig- 

 mata, bearing spores in chains up to 100/x in length, becoming tangled in 

 age; sterigmata mostly 10 to 12/^ by 2.0 to 2.5m, occasionally 15m in length, 

 commonly showing one or more under-developed cells in the verticil, 

 tapering to rather broad conidium-producing tubes; conidia at first long, 

 obpyriform to apiculate, often continuing so, more commonly becoming 

 elliptical, 4.0 to 5.0m by about 3.0m, with walls smooth or finely granular. 



Colonies on steep agar up to 3 cm. in diameter after 10 to 12 days at 

 room temperature, velvety and wrinkled as on Czapek, azonate, reverse 

 in darker shades of orange-yellow near vinaceous fawn (R., PI. XL); 

 penicilli as described above. 



Colonies on malt agar 2 to 3 cm. in diameter in 10 to 12 days, looser 

 textured and showing some trailing hyphae, less strongly wrinkled, more 

 heavily sporing throughout; no odor; no exudate; reverse in golden brown 

 shades ; penicilli as described above but with sterigmata sometimes appear- 

 ing irregular and with spore-bearing tubes longer, conidia usually long 

 pyriform. 



Species description centered upon a culture received in July 1946, from 

 the Centraalbureau as a culture from Biourge bearing this name, pre- 

 sumably type, obtained by them in 1929. This culture is now maintained 

 in our collection as NRRL 2071. Occasional strains produce colonies in 

 darker yellow-green colors with reverse less strongly pigmented. NRRL 

 2072, received from Professor Weston as an isolate from deteriorating mili- 

 tary equipment, Barro Colorado Island, Panama Canal Zone, is repre- 

 sentative of these forms. 



Biourge's species is recognized since his culture seems to represent, 

 fairly well, a group of strains having the general cultural characteristics 

 of the Penicillium implicatum series but producing large elliptical to obo- 

 vate or pyriform spores. Proper placement of the species can only be 

 guessed from Biourge's original description and figures. Thom in 1930 

 regarded it as no more than "a variety of the P. frequcntans series of 

 organisms". If the culture in our possession is authentic, this earlier assign- 

 ment is regarded as untenable, since the culture in question differs mark- 

 edly from P. frequentans in rate and pattern of growth, in size, and struc- 

 ture of the penicillus, and particularly in the dimensions and shape of the 

 conidia. Conidial areas usually run toward yellow or gray-green rather 



