490 A MANUAL OF THE PENICILLIA 



Members of the series appear to be abundant upon stored grain, par- 

 ticularly corn. Koehler (1938) reported Penidllium viridicatum and P. 

 paUtans capable of growing upon shelled corn at moisture levels of 17.6 

 per cent and 18.0 per cent, respectively. The latter species produced typi- 

 cal "blue-eye" damage, i.e., developed abundant fruiting structures be- 

 tween the germ and seed coat, at 19.5 per cent moisture. Semeniuk and 

 Barre (1944), investigating corn stored in steel bins in Iowa, found P. viri- 

 dicatum to be the chief mold present, although Aspergillus flavus and A. 

 glaucus were also reported. Marchionatto (1942a), working in Buenos 

 Aires, found a Pe7iicillium, identified by Thom as P. viridicatum, prevalent 

 upon maize infected with "mildew". Such grain was reported to the Ar- 

 gentina Ministry of Agriculture as the cause of poisoning of pigs and horses. 

 In a second report (1942b) both P. viridicatum and P. olivino-viride were 

 noted as common on "moldy" maize, whereas A . /ay ws was most abundant. 



Penicillium viridicatum and P. palitans are sometimes isolated from 

 rotting pomaceous fruits, although they do not cause a destructive rot com- 

 parable to that produced by P. expansum (see p. 518). 



Members of the series likewise occur upon fat and protein rich substrata. 

 Stokoe (1928), investigating the rancidity of coconut oil caused by Peni- 

 cillium palitans found this to be largely due to the presence of various 

 methyl ketones. Ledingham (personal correspondence) isolated members 

 of the present series from plates exposed in a meat packing plant. Three 

 of the four strains of P. palitans studied by Birkinshaw and Raistrick 

 (1936) were isolated by Neill from discolored New Zealand cheddar cheese. 



Birkinshaw and Raistrick (1936a) reported the production by strains 

 of Penicillium palitans of a hitherto undescribed metabolic product, desig- 

 nated palitantin, C14H22O4. Upon Raulin-Thom medium, the substance 

 was produced by the type of the species, received from Baarn, and by 

 Neill's three isolates (cited above), which had been received as P. puheru- 

 lum Bainier. Maximum yields were obtained at low temperatures from 

 10° to 18°C. Palitantin was shown to be an unsaturated dihydroxyalde- 

 hyde. The preparation of various derivatives and oxidation and reduction 

 products was described. 



Penicillium cyclopium Series 



Outstanding Characters 



Colonies are characterized by conidial areas in blue-green (aeruginous) 

 colors in which the blue element predominates, or is at least clearly evi- 

 dent, and a sufficient proportion of the conidiophores are generally ag- 

 gregated into fascicles to give the colony surface a granular or tufted 

 appearance, at least in marginal areas. Colonies in reverse often show 



