496 A MANUAL OF THE PENICILLIA 



and NRRL 1888 from George Smith, London School of Hygiene and 

 Tropical Medicine, as their No. 123, a culture of P. cydopium found by 

 Raistrick and associates (1936) to produce penicillic acid. 



Penicillimn cydopium is reported from many different substrata and is 

 world-wide in distribution. It has appeared in Holland and in the United 

 States as the dominant mold in rotting bulbs belonging to the lily family, 

 attacking and destroying the growing point. It is among the more com- 

 mon forms submitted for identification by collaborators and has been 

 isolated from ^'arious types of ripe or aging fruit, grain and cereal products, 

 soil and decajdng vegetation, bee hives, mildewing tentage, etc. As de- 

 scribed above, the species embraces a wide range of isolates or strains 

 which vary one from another in particular cultural or microscopic details, 

 yet are characterized by their "granular colonies" of rather dull blue-green 

 color, finely roughened conidiophores (on Czapek agar), and predominantly 

 subglobose spores. 



Penicillium conditaneum Westling (Arkiv for Botanik 11: 52, 63-65, figs. 46 and 2. 

 1911) was isolated from Rihes nigra and described in terms which ally it with P. cydo- 

 pium Westling as indicated by Thorn's placement of the species in his Monograph 

 (1930). Unfortunately the type strain has been lost from collections, and there was 

 no material available for this study that could be regarded as representing with cer- 

 tainty Westling's concept of his species. Re-examination of Thorn's notes on West- 

 ling's type strain (Thorn No. 2538) leads us to believe that P. conditaneum hardly 

 represented more than a strain difference. This species is, therefore, regarded as a 

 probable synonym of P. cydopium, which is rather generally recognized. 



Penicillium aurantio-griseum Dierckx (Soc. Scien. Bruxelles 25: 88. 1901. See 

 Biourge, Monogr., La Cellule 33: 126-128; Col. PI. I and PI. II, fig. 8. 1923) was 

 described by Biourge in terms which place it with P. cydopium as this species is con- 

 sidered here. Examination of the type strain, NRRL 971 (Thom No. 4733.7), in the 

 present study confirms such placement. Colonies are somewhat restricted, 2.0 to 2.5 

 cm. in 10 to 12 days, but otherwise typical of the series. Conidia are more consist- 

 ently elliptical than in such typical strains of P. cydopium as NRRL 1888 and 1899 

 (see above) , hence more nearly approach P. mariensii. Other characters more nearly 

 duplicate those of P. cydopium. We believe P. aurantio-griseum Dierckx should be 

 regarded as a member of the P. cydopium series but showing insufficient strain 

 individuality to warrant continued species recognition. 



Penicillium aurantio-griseum Dierckx var. poznaniensis Zaleski (in Bui. Acad. 

 Polonaise Sci.: Math, et Nat. Ser. B, pp. 444-445, Taf. 37. 1927), as known by a 

 strain received from Zaleski under this name, represents a member of the P. cydo- 

 pium series approximating the species P. cydopium Westling except colonies are 

 hardly fasciculate upon any culture medium. The strain produces strong earthy 

 odors characteristic of the species; conidiophores are rough-walled, and peni- 

 cilli commonly show a rather compact branching system. This latter character led 

 Thom (1930, pp. 301-302) to place the variety in the P. brevi-compactum series. Other 

 considerations, however, seem to outweigh this, and the form is believed to be more 

 correctly placed in the Fasciculata, 



