ASYMMETRICA-DrVARICATA 263 



torial areas marked by two low, widely separated ridges and smooth 

 sidewalls. Each of these species produce penicilli usually consisting of a 

 terminal cluster of 3 to 4, often divergent, metulae. Monoverticillate 

 structures occur in considerable numbers in all cases. 



The above species seem to bear a definite relationship to Penicillium, 

 javanicum and allied species and it is possible that the two series should 

 be considered together as comprising a single natural group. This is 

 indicated by a striking u'esemblance in the appearance and in the develop- 

 mental history of the perithecia in the two series. While we have made no 

 detailed histological study of perithecium formation in these forms, our 

 observations of plate cultures on many different substrata confirm 

 Emmons' report (1935) that the perithecia of P. asperum and P. egyptia- 

 cum oi-iginate and develop in the same manner as described by Dodge 

 (1933) for P. hrejddianum (see p. 133). Close relationship is further 

 indicated by the frequent, though possibly atypical, development of bi- 

 verticillate penicilli in some members of the monoverticillate P. javanicum 

 series, and by the freciuent occurrence of monoverticillate structures in 

 the biverticillate Carpenteles series. As a matter of convenience, we have 

 separated ascosporic species with definite walled perithecia into two series 

 upon the type of penicillus usually produced, but this treatment may prove 

 too arbitrary. Only by the isolation and examination in culture of ad- 

 ditional members of both series, as they are now constituted, can the true 

 relationships of these ascosporic forms be established. 



Members of the Carpenteles series likewise bear a striking resemblance to 

 Penicillium raistrickii and allied sclerotial forms in the general pattern of 

 their penicilli. In fact, they differ from the latter primarily in the forma- 

 tion of asci and ascospores, a development which commonly occurs late 

 and not infreciuently fails of completion. There is little morphological 

 difference to distinguish a typical strain of P. raistrickii from a strain of 

 P. aspermn that fails to develop ascospores, except the coarsely roughened 

 conidiophores of the former species. 



Penicillium asperum (Shear) n. comb. 

 Synonym: Carpenteles asperum Shear, in Mycologia 26: 104-107, figs. 

 1-3. 1934; also Emmons, in Mycologia 27: 146, figs. 15 

 and 16. 1935. 



Colonies on Czapek's solution agar rather slow growing, attaining a 

 diameter of 2.5 to 3.0 cm. in 10 to 12 days at room temperature, in age 

 almost covering the culture plate, strongly wrinkled and buckled at least 

 in central area, comparatively thin, consisting of a tough, fairly brittle 

 basal felt, with surface growth thin and fibrous, usually producing very 

 few conidial structures within one to two weeks or longer; at first white, 



