ASYMMETRICA-FUNICULOSA 455 



entirely possible that these may constitute a natural series in which colonies 

 assume characteristics that are more apparent than fundamental, with 

 P. puberulum producing colonies typically velvety but sometimes showing 

 fasciculation ; P. cyclopium, typically fasciculate but sometimes velvety; 

 and P. solitum, typically funiculose but sometimes developing true fas- 

 cicles or again appearing almost velvety and regularly producing conidial 

 structures of the general habit and pattern of the other two species. 



Penicillium resticulosum Birkinshaw, Raistrick, and Smith in Biochem. 



Jour. 36: 829-835. 1942. 



Authors' diagnosis: 



"Colonies on Czapek agar spreading broadly, tenuous, at first white then pale 

 bluish green with very broad funiculose margin, becoming fairly dark grey -green all 

 over, floccose-funiculose, especially in outer areas, broadly and indistinctly zoned in 

 old cultures; drops numerous during the growing period, small, pinkish; reverse 

 quickly reddish brown to chestnut brown, shading to dull yellow near the margin; 

 conidiophores long, mostly loosely aggregated in ropes rather than in true fascicles, 

 smooth, .3-4ju in diameter; penicilli very compact, 2-3 verticillate, often with main 

 axis bearing a terminal verticil of metulae and sterigmata and one or two appressed 

 secondary branches bearing sterigmata at approximately the same level as the main 

 axis, up to 100m ii^ total length; metulae somewhat clavate or definitely swollen at the 

 tip, 14-19 by 3-3. 5/i (4.5ju at tip); sterigmata O-lO/x x 2.2-3.0m, widening upward then 

 tapering abruptly to fine points; conidia cut off as more or less citriform segments, 

 often resembling chains of oidia, subglobose when ripe, smooth, 3-4 x 2.8-3.2/x; co- 

 nidial chains at first roughly parallel, in old cultures becoming much tangled. 



"Cultures on wort agar remain sterile for several weeks if kept in the dark but well 

 established colonies may be induced to form abundant spores by exposure for a few 

 hours to diffuse light. 



"Related to Penicillium terrestre Jensen and P. solitum Westling, but differing 

 from both in texture of colonies and in colour. 



"Found as a culture contaminant in the laboratory. The name chosen for the new 

 species is descriptive of the colony texture". 



The type strain, NRRL 2021, was received from George Smith, London 

 School of Hygiene and Tropical Medicine, in November 1945 as 

 L.S.H.T.M. Catalogue No. P-47. 



Our notes on cultures of the type strain follow : 



Author's description of colonies on Czapek's solution agar is carefully 

 and accurately drawn (fig. 118A), and the general description of the peni- 

 cillus is correct (fig. 11 8C), but metulae are somewhat shorter than re- 

 ported, sterigmata are not particularly pointed, and conidia appear defin- 

 itely elhptical when ripe. 



Colonies on steep agar grow somewhat more rapidly than upon Czapek, 

 completely covering the culture plate in 12 to 14 days (fig. 118B), and are 

 generally more funiculose (fig. 118D). 



