MONOVERTICILLATA 217 



spoiulating abundantly over the whole colony surface from a basal myce- 

 lial felt yellow in color and in texture as described above, conidial color 

 as on Czapek but quickly changing to gray shades in central area and be- 

 coming mouse gray in age; exudate more abundant; reverse and agar in 

 yellow shades, becoming orange-brown under central colony areas; peni- 

 cilli as described above. 



Colonies on malt extract agar spreading fairly broadly, 4.0 to 5.0 cm. 

 in 2 weeks, plane, slightly zonate, or azonate (fig. 60C), heavily sporing 

 throughout, color as in sporulating areas on Czapek; reverse in dull yellow- 

 brown to red-brown shades; conidial structures as described above. 



Species description based upon our observations of NRRL 1187, NRRL 

 2046, NRRL 2047, and other strains having similar morphology combined 

 with Thom's original notes (see Monograph, 1930, p. 200) made from 

 Biourge's type strain, now lost from our Collection. The species has 

 appeared repeatedly among cultures isolated from deteriorating military 

 equipment submitted to us for identification, and strains NRRL 2046 

 and 2047 are of this origin. The species should he. regarded as a soil 

 organism widely distributed in nature. It is apparently able to grow 

 under conditions of limited moisture and nutrients that would exclude 

 many faster growing species. 



Representatives of this species, as examined by us, vary substantially 

 in gross cultural appearance, in relative abundance of sporulation, and 

 to a lesser degree in details of morphology. There is reason to believe 

 that earlier workers may have based species description upon variants 

 or strains now known to represent different aspects of the same species 

 complex. Five such species are believed to represent PeniciUium citreo- 

 viride Biourge as this species is regarded here. 



PeniciUium cilreo-nigrum Dierckx, (Soc. Scient. Bruxelles 25: p. 86. 1901; also 

 Biourge's Monograph, La Cellule 33: fasc. 1, pp. 273-274, Col. PI. IX and PI. XV, fig. 

 87. 1923) as represented by NRRL 761 (Thom's No. 4733.35), received from Biourge 

 under this name in 1924, duplicates P. citreo-viride except colonies are thinner and 

 somewhat faster growing, margins tend to be thin and often more or less submerged 

 in a zone 2 to 3 mm. wide; but the general colony texture and coloration, and the 

 structure of the penicillus are as described above. A culture from the Centraal- 

 bureau under this name, originally from Biourge and presumably of the same origin, 

 duplicates even more exactly the cultures here regarded as representing P. citreo- 

 viride. In the absence of any substantial differences in the original descriptions of 

 P. citreo-viride Biourge and P. citreo-nigrum Dierckx as reported by Biourge, we 

 believe that the latter should properly be regarded as a synonym. Our description 

 of P. citreo-viride Biourge is accordingly drawn in broad enough terms to include the 

 two cultures in question. 



PeniciUium cilreo-sulfuratum Biourge (Monograph, La Cellule 33: fasc. 1, pp. 285- 

 287, Col. PI. IX, and PI. XV, fig. 86. 1923) is believed to be synonymous with his 



