606 A MANUAL OF THE PENICILLIA 



Colonies on steep agar growing more rapidly, attaining a diameter of 

 3.5 to 4.5 cm. in 2 weeks at room temperature, ^^■itll margins more regular 

 than above, often entire, with surface appearing slightly granular from 

 abundant perithecia or almost velvety where these become confluent, at 

 first white, becoming buff to light brown in central areas in age; exudate 

 very limited, clear; reverse in dull to reddish brown shades; penicilli very 

 limited in number; perithecia very abundant, often forming a continuous 

 laj'er; ascospore development and measurement as above. 



Colonies on malt agar spreading broadly, attaining a diameter of 6.0 to 

 7.0 cm. in 2 weeks, thin, plane (fig. 157B), conspicuously granular in ap- 

 pearance with perithecia in a dense layer at the agar surface and surrounded 

 by a thin loose network of vegetative hyphae; reverse ranging from dull 

 brown to purple; penicilli sparsely produced; perithecia ripening within 

 10 days. 



Colonies on 20 per cent sucrose-Czapek agar thin-growing, restricted as 

 on standard Czapek but producing penicilli in limited numbers but more 

 abundantly than on the above media ; penicilh irregular in pattern and com- 

 plexity (fig. 156 A and B), commonly monoverticillate but often developing 

 as biverticillate structures without consistent arrangement of parts; conidio- 

 phores mostly short, 50^ or less, borne as branches from aerial hyphae, 

 occasionally arising from the substratum and lOO/i or more in length, 

 smooth -walled, about 3.0m in diameter; penicilli simple, monoverticillate 

 and usually consisting of a terminal verticil of 3 to 5 or 6 sterigmata (fig. 

 I56A3), or biverticillate with 2 or more metulae or branches arising at a 

 single or different levels (fig. 156B), 8 to 10m or more in length by 3.0 to 3.5m 

 in diameter, occasionally almost ramigenous consisting of a number of short 

 divergent, irregularly arranged branches bearing sterigmata; sterigmata 

 variable in form and dimensions but mostly 8 to 10m by 2.5 to 3.0m with 

 conidium-bearing tips short and definitely narrowed; conidia quickly de- 

 ciduous, elliptical, mostly 3.0 to 4.0m by 2.5 to 3.0m, with ends usually 

 somewhat pointed, walls smooth and comparatively heavy. 



Species description centered upon a culture, now maintained as NRRL 

 717, isolated in 1938 by Williams, Cameron, and Wilhams (1941) from 

 canned blueberries. A second strain, NRRL 2080, was isolated in January 

 1946 from a sample of soil from Sweden sent to us by Professor Edy Velan- 

 der. This latter culture differs from the above only in producing colonies 

 slightly more restricted and ascospores with flanges less consistently paral- 

 lel. A third strain similar to the second was isolated from Swedish soil 

 but was not retained. 



The proper placement of PeniciUiurn striatum remains in doubt. The 

 general characteristics of its perithecia are strongly suggestive of the genus 



