ASYMMETRICA-DIVARICATA 329 



3 new species. We have examined carefully the original description, and 

 cultural observations made by Thom on Zaleski's strains prior to the 

 IHiblication of his Monograph in 1930. We have likewise re-examined the 

 type strains in connection with the present study and we are led to believe 

 that two of his three species represent merely normal strain divergence in 

 the abundant and variable species, Penicillium nigricans (Bainier) Thom. 



Penicillium siviecickii Zaleski (Bui. Acad. Polonaise Sci.: Math, et Nat. Ser. B 

 pp. 474-476; Taf. 51. 1927) was described by Zaleski as having smooth-walled conidia 

 about 2.3 to 2.8jli in diameter. The strain received as type from the Centraalbureau 

 in July 1928, as noted by Thom (1930) produced spinulose conidia 3.0 to 3.5/1 in diam- 

 eter. Re-examined in the present study, Thom's earlier observations are confirmed 

 but the conidia are not so conspicuously roughened as in typical members of the 

 series, nor is the deposition of coloring matter as heavj' as in most forms. The cul- 

 ture is regarded as a variant form of P. nigricans and it is believed that P. swiecickii 

 Zal. should be regarded as a synonym. 



Penicillium janczewskii Zaleski (Bui. Acad. Polonaise Sci.: Math, et Nat. Ser. B, 

 pp. 488-490, Taf. 55. 1927). Zaleski's description of this species and Thom's obser- 

 vations on the type strain received through the Centraalbureau fail to provide ade- 

 quate bases for separation from P. nigricans. This was implied bj^ Thom in 1930, 

 in his consideration of the P. nigricans -janczewskii series. Examination of the type 

 strain in the present study clearly reveals its identity with P. nigricans (Bainier) 

 Thom. The culture differs from typical strains of P. nigricans only in producing 

 colonies of somewhat closer texture and little or no j'ellow coloration in reverse. 

 The irregular and divaricate penicilli and the conspicuously echinulate conidia are 

 indistinguishable from those of P. nigricans (Bainier) Thom, with which Zaleski's 

 species should be regarded as synonymous. 



Penicillium alhidum Sopp, in Monogr. pp. 186-187, Taf. XXI, fig. 144; 



Taf. XXIII, fig. 33. 1912. Thom, The Penicillia, 



pp. 350-351. 1930. 



Sopp's description and figures for this species would seem to closely ally 

 it with Penicillium nigricans. The conidia are described as "thorny" 

 or rough, and at first green in color but soon becoming olive-green to gray 

 and finallj^ brown; colonies show surface growth uneven, fibrous, and con- 

 sisting of irregularly branching and trailing hyphae, reverse is in reddish 

 yellow shades. Thom (1930) discussed a strain (now lost from the Col- 

 lection) under this name and placed the species in his P. nigricans-jan- 

 czewskii series. A strain recently received from the Centraalbureau as an 

 isolation of this species by Janke shows colonies essentially white, fioccose, 

 and with surface more or less uneven; conidial structures are very small 

 and fragmentary, and consist almost exclusively of sterigmata borne 

 separately or as strongly divergent spore-bearing cells. The conidia are 

 conspicuously roughened, globose, and measure about 3.0 to 3.5/i, rarely 

 4.0/x. Except for the absence of well-formed divaricate penicilli, which 



