220 A MANUAL OF THE PENICILLIA 



margins, since individual strains are known to vary appreciably in this 

 regard depending upon the substratum employed and other environmen- 

 tal factors. 



Representative strains of PeniciUium roseo-purpureum are occasionally 

 isolated from soil and have been encountered among the isolates from 

 deteriorating military equipment sent to us for identification. The 

 species appears to be cosmopolitan, but not abundant, in nature. 



The following species are believed to be inseparable from PeniciUium 

 roseo-purpureum Dierckx as that species is regarded here: 



PeniciUium carmino-violaceum Dierckx (Soc. Scieiit. Bruxelles 25: 86. 1901. 

 Biourge, Monograph, La Cellule 33: fasc. 1, pp. 281-282; Col. PI. X and PI. XVI, 

 fig. 93. 1923) is believed to approximate P. roseo-purpureum Dierckx as described 

 above. Biourge 's description reported some ropiness, and Thorn's observations on 

 his strain (Thorn's No. 47.33.28) records this character for the aerial growth but other- 

 wise fails to provide adequate basis for distinguishing the species from P. roseo-pur- 

 pureum. NRRL 733, cited by Thorn in his Monograph (1930, p. 192) as No. 4733.83 

 and representative of P. carmino-violaceum agrees satisfactorily with P. roseo-pur- 

 pureum as diagnosed above. It produces few conidial heads and develops some red- 

 dish pigmentation, especially in the exudate. 



Citromyces sanguifluus Sopp (Monograph, pp. 115-117, Taf. XV, fig. 105; Taf. 

 XXII, fig. 3. 1912) is believed to have represented a form approximating PeniciUium 

 roseo-purpureum Dierckx. Colonies were reported as tough, leathery, folded and 

 wrinkled, producing loosely velvety, pale greenish conidial areas and exuding abun- 

 dant blood red drops of exudate, with reverse at first yellowish red becoming deep red 

 to almost black in age. Penicilli are figured as monoverticillate (approaching 

 ramigenous) with conidia small, globose, and smooth. Biourge regarded the species 

 as a synonym of P. roseo-purpureum Dierckx, a placement in which we concur. 



PeniciUium internum Morotchkovsky (Bui. Sci. Recueil Biol. Univ. Kiev. 2: 78- 

 79, fig. 8. 1936) is believed to represent a lightly colored form approximating P. 

 roseo-purpureum Dierckx. The type has not been seen by us. A translation of the 

 author's latin diagnosis follows: Colonies white, floccose; reverse uncolored or yellow; 

 margin narrow, smooth; sterile hyphae hyaline, few septate, branched; conidiophores 

 creeping, resembling sterile hyphae, more or less flexuous, branches 2.7 to 3.0m in di- 

 ameter, unseptate, minutely granulose within; sterigmata differing in form and size, 

 8.5 to 11.0m t>y 2.0 to 2.5m, mostly in two's or three's; conidia smooth, colorless, glo- 

 bose, 2.7 to 3.0m, quickly falling away. Isolated from the fibrovascular bundles of 

 the root of a sugar beet. 



Occurrence and Significance 



Members of the PeniciUium decumbens series represent normal com- 

 ponents of the mycofiora of most soils and commonly develop upon a wide 

 variety of organic substrata if subjected to soil, dust, or water-borne 

 contamination. They are world-wide in distribution, and appear to be 

 unusually prevalent in tropical and subtropical areas. Since they grow 

 so restrictedly in artificial culture, hence are easily overgrown and ob- 



