546 A MANUAL OF THE PENICILLIA 



type of culture formed the basis of Bainier's description except that it was 

 strongly coremiform, possessed granular walls, and produced conidia el- 

 liptical to globose. Thorn's notes, published in 1910, from Bainier's type, 

 defined more precisely the limits of the species but these were made from 

 culture media seldom used in the present mycological laboratory and thus 

 render strict interpretation difficult. 



Penicillium granulatum., as the species is considered here, makes its most 

 characteristic development upon malt extract agar. Coremia are gener- 

 ally larger and more clearly defined than upon other substrata; conidio- 

 phores and elements of the penicillus are more strikingly granular ; and the 

 production of odors regarded as characteristic of the species reach their 

 maximum intensity. These odors are consistently fragrant and aromatic 

 and are variousl}' diagnosed as odors of over-ripe apples, cooked pineapple, 

 mature walnut husks and occasionally a medicinal odor suggestive of a weak 

 iodine solution. 



The feathery fruiting mass that is fairl}- characteristic of this species re- 

 sults from the div^ergence of the individual penicilli which comprise the 

 fascicle or coremium. In contrast, Penicillium daviforme, next to be con- 

 sidered, produces large and compact coremia in which the identity of 

 individual conidial structures is seldom recognizable. 



In general colony appearance, Penicillium granulatum is distinguished 

 from P. expansum by much larger coremia, and by conidiophore walls 

 that are conspicuously roughened. Strains are occasionally encountered 

 which appear transitional between these two species. Representative of 

 such forms is NRRL 974 received in 1922 from the Bainier Collection 

 labelled P. virescens. Growing on Czapek agar, this strain is strongly 

 suggestive of typical P. expansum but stalk walls are conspicuously rough. 

 On malt agar, colonies produce more prominent coremia and conidiophores 

 are often coarsely granular, approaching the characteristic picture of P. 

 granulatum. The strain does not cause an active rot in pomaceous fruits 

 and we believe it is more satisfactorily assigned to the latter species. 



Penicillium divergens Bainier and Sartory (Bui. Soc. Mycol. France 28: 270-276, 

 PI. XIII, figs. 3-6. 1912.) was described in terms which make its separation from 

 P. granulatum very doubtful. Published figures of this species substantiate the basic 

 similarity of the two forms. Since both species were described by Bainier, we can 

 assume that some differences between the types of the two were observed. We do 

 not believe that the differences as reported are sufficient to warrant the continued 

 retention of both names. It is probable that they represented no more than normal 

 strain variations which we now recognize as being characteristic of all species of 

 Penicillia. Penicillium divergens, the last name proposed, is regarded as a synonym. 



Penicillium schneggii Boas (Myc. Centbl. 5: 73-83. 1914; and Centbl. Bakt. etc., 

 (II) 44: 695-696. 1916; also Thom, The Penicillia, pp. 415-416. 1930) was originally 

 described in terms which clearly relate it to the P. granulatum series: Coremia ranged 



