BIVERTICILLATA -SYMMETRICA 633 



became, in effect, a catch-all for almost any conidial member of the Biver- 

 ticillata-Sj^mmetrica which was not marked by a strong pigmentation, or 

 the development of conspicuously funiculose, strongly restricted, or ex- 

 ceptionalh' thin colonies. While some of the strains now assigned to P. 

 verruculoswn Peyronel in the P. funiculosum series were originally assigned 

 to Thom's non-ascosporic P. luteum series, the latter was represented 

 primarily by strains which we now include in P. variabile Sopp and place 

 in the P. purpurogenum series. 



Penicillium purpurogenum Stoll, in Beitrage zur morphologischen und biol- 

 gischen Characteristik von Penicilliumarten, Wurzburg, p. 32, Taf. 1, 

 fig. 6 and Taf. Ill, fig. 2. 1904; see also Thom, U. S. Dept. Agr., Bur. 

 .\nim. Ind., Bui. 118, p. 36, fig. 5. 1910; Mycologia 7: 134-142. 1915; 

 and The Penicillia, pp. 478-479. 1930. 



Colonies on Czapek's solution agar (Col. PL X) growing rather restrict- 

 edly, attaining a diameter of 1.5 to 2.5 cm. in 12 to 14 days at room tem- 

 perature (fig. 162A and E), sometimes definitely wrinkled, zonate or azon- 

 ate, consisting of a yellow to orange-red mycelial felt bearing abundant 

 conidial structures, or of massed conidial heads arising from aerial hyphae 

 or directly from the substratum and superficially appearing velvety, or in 

 some strains tending to become floccose with growing margin white or 

 3^ellowish from an admixture of encrusted sterile hyphae; usually heavily 

 sporing in central and sub-central areas, in deep yellow-green shades near 

 lily green through deep slate green to dull greenish black (Ridgwaj', PI. 

 XLVII); exudate usually limited but in some strains fairly abundant, in 

 orange-red shades; odor indistinct or slightly moldy; reverse in deep red 

 to dark reddish purple shades, often approximating ox blood red (R., 

 PL I), with surrounding agar similarly colored in somewhat lighter shades; 

 conidiophores arising from the substratum and measuring up to 100 to 150/i 

 in length by 2.5 to 3.0 or 3.5/x in diameter, or as branches from aerial 

 hyphae and much shorter, about 40 to 50/x, smooth- walled ; penicilli typi- 

 cally biverticillate and sj'-mmetrical (fig. 162C and D), compact, usually 

 consisting of a single verticil of 5 to 7 or 8 metulae, each terminating in a 

 compact cluster of 4 to 6 parallel sterigmata bearing short conidial chains; 

 metulae 10 to Hn by 2.5 to 3.0^; sterigmata mostly 10 to 12jLi by 2.0 to 

 2.5m, lanceolate in form, characteristically tapered; conidia elliptical to sub- 

 globose in some strains, sometimes more or less apiculate, mostly 3.0 to 

 3.5m by 2.5 to 3.0m with walls typicalh^ heavy and irregularly roughened, 

 sometimes showing distinct transverse bands, but in some strains almost 

 smooth. 



Colonies on steep agar spreading broadly up to 5.5 to 6.0 cm. in 12 to 

 14 days at room temperature, comparatively thin, plane or lightly fur- 



