1894.] Cultures of Isaria farinosa. 133 
spores had by this time germinated, one to two or three 
tubes having arisen from a single spore. Branching also by 
this time was taking place quite freely. Rather faint vacu- 
oles appear in the thread at quite regular intervals as if in the 
middle of the cell, the transverse walls of which are hard to 
distinguish in the agar. By December 31st the growth had 
increased sensibly and the branching was becoming quite 
profuse while some of the shorter branches were being elevated 
in the air, but there was as yet no evidence of spore forma- 
tion. 
When the colonies become perceptible to the unaided eye 
the surface ones are circular, quite compact, and with very 
fine humerous radiating lines on the margin, giving it a finely 
fimbriated appearance. When young the deep seated colo- 
hes are apt to be angular so that many of them are triangu- 
lar in form. Asthe colonies age the superficial ones, or those 
which reach the surface by later growth, become convex 
y the elevation of numerous threads which give it a 
whitish fluffy appearance at the center, while at the margins 
it is still finely fimbriate from the radiating threads. While 
oe are quite young they resemble those of a species 
encillium, probably P. glaucum, which appeared acci- 
ainsi no. 3. In plate xIv, figs. 2,3, 4, this 
sie colony of Penicillium can be easily differentiated from 
rey i. a, but in fig. I it is impossible to do so 
Ot ag the corresponding location of the colony in 
Ri dish rf € four photographs of the cultures being from the 
eoloiay frase fo ove stages ofgrowth. Whenthe Penicillium 
80 arrange Ta € Sporophores are quite long and erect and are 
: at open spaces appear here and there through 
Which the ]j h 
- t i 
strong diffe age more easily than at other places and a 
P 
m they become mealy white in appearance 
of er a of spores produced, mixed with the mass 
i naar The appearance of the colonies may be 
temper at by periodic growth, induced by variations 
— Clture ng. ature. Some tests of this were made with the 
3 ' 3 of the dilution for the separation of the fungus. 
