IR ge EN eh a aT SE Re Tere aCe Smee pete hae ret 
RPE eee! PUT eee NO eee Tene em been ee 
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1900] BRIEFER ARTICLES 53 
numerous instances have been observed in which no such outgrowths 
could be seen, the secondary conidia having every appearance of being 
given off directly from the germ tube or even from the conidium 
itself. They are at first hyaline, later with a greenish tinge, granular, 
elliptical, rarely slightly curved, and always, so far as observed, 
decidedly smaller than the original conidium, although 
varying greatly with the character of the food supply. 
The most abundant production of these secondary 
conidia is in the immediate vicinity of the conidium, 
so that there is a tendency to produce an acervulus. 
: In three or four days the stellate colo- 
nies become visible to the unaided eye. 
They are circular in shape, with a slight 
grayish tinge, elevated and somewhat 
darker in the center, where the production 
of secondary conidia is most 
abundant. In crowded cultures 
they rarely become more than 
2—3"" in diameter, but under more favor- 
able conditions may attain a diameter of 
4-8™. In its earlier stages the mycelium, 
which radiates quite uniformly in all 
directions from the center, is sparingly 
septate and without vacuoles. In the 
older colonies it becomes vacuolated, and has been 
observed to break up into chains of irregular thick- 
walled, dark-colored cells. 
In order to check the results, cultures on bean 
ae 8. times. October 10 two colonies, which were supposed 
to have developed from the Gloesporium spores, were 
transferred from Petri dish cultures to tubes of sterilized acid bean stems. 
October 12 the conidia from a single acervulus were teased out in steril- 
‘zed water, and with the tip of a sterilized needle a very few spores 
were transferred to each of several tubes of bean stems. October 17 
‘IX More colonies were transferred from plate cultures to tubes of bean 
stems, and four days later four more tubes were inoculated by transfer- 
— colonies which had been grown in cell cultures. On the 17th a 
dilution color was made in acid potato-agar. On the 18th, after the 
