222 A MANUAL OF THE PENICILLIA 



were indistinguishable in color. Carviolin is insoluble whereas carviola- 

 cin is somewhat soluble in cold water. Both are soluble in ethyl alcohol 

 and acetone. Carviolin crystallizes as chrome colored needles, M.P. 286°. 

 Carviolacin crystallizes as greenish fluorescent plates, M.P. 204° with a 

 tendency to sublime above 185°. The preparation of various crystalline 

 derivatives of these pigments was described. Ergosterol was extracted 

 from the dried mycelium and recrystallized from alcohol. 



Prior to this Krause and Ellis (1937), studying the inhibitory effects of 

 ethyl and methyl alcohols on spore germination in different Penicillia, 

 had reported two pigments to be produced by Penicillium carmino-viola- 

 ceimi and noted that one of these acted as an indicator. They did not, 

 however, isolate or characterize these pigments, and their identity with 

 those subsequently reported by Hind is open to question. 



Penicillium restrictum Series 



The Penicillium restrictum series is admittedly artificial in concept and 

 is designed to cover certain forms which cannot otherwise be satisfactorily 

 placed. Two species are included, namely: P. restrictum Oilman and 

 Abbott and P. fuscum (Sopp) n. comb. Close relationship between the 

 species included is not presumed, and they are considered together pri- 

 marily as a matter of convenience. They do, however, show certain fea- 

 tures in common, particularly coarsely roughened, globose conidia and a 

 tendency to develop floccose colonies, which enables them to be keyed 

 together and to be separated from the other monoverticillate Penicillia in 

 the manner shown in the general key to this group (see p. 131). 



Penicillium restrictum is of considerable interest because of its possible 

 transitional position between the two genera, Penicilliimi and Aspergillus. 

 Strains presenting the cultural and microscopical picture of a true mono- 

 verticillate Penicillium are sometimes observed. Structures associated 

 with this specific name, however, are often produced by strains which, 

 upon especially favorable media, produce conidial heads characteristic of 

 Aspergillus sydowi in greater or less abundance. Thom and Raper, in 

 their "Manual of the Aspergilli" (1945, p. 186), called attention to this 

 occurrence and suggested that P. restrictum Oilman and Abbott should 

 probably be assigned to the A. versicolor group along with A. sydowi. 

 While we still regard this assignment as probably correct, we recognize 

 that retention of the name is necessary to account for certain strains 

 wherein the more complex, aspergilloid conidial apparatus does not appear 

 and the smaller, fragmentary, penicillate structures characterize the 

 culture. 



Penicillium fuscum (Sopp) n. comb., as considered here, is believed to 



