82 
appears that their order of nutritive value for this fungus, from poorest 
to best, is 100°, 43°, 85°, 60°. Evidently a temperature of 43° is in- 
sufficient to extract the nutrient proteids sufficiently, while 100° pre- 
cipitates too many of them. While leucosin, a prominent proteid of the 
embryo, is largely precipitated at 52° and a second coagulum goes down 
at 82°, no more is precipitated even by boiling (Osborne, 89). 
Graphs 1-4 (Fig. A), indicating conidial length on these four agars, 
show that although the quantity of conidia produced varied materially, the 
length and general variability are not greatly influenced by varying the 
composition of the agar—done in this case by change of temperature. 
The conidial length of all these agars is, however, considerably less than that 
on wheat shoots (cf. graphs in Fig. A and Fig. K). Graphs of conidial 
breadth and septation on 43° and 60° agars given in Fig. B also show but 
little influence of these agars on these two characters. <A ‘‘Difco’’ corn- 
meal agar, prepared according to my directions by the Digestive Ferments 
Company, gave growth-characters almost identical with those of my 
own 60° agar. On “Difco” beef-agar the conidia were short, and were 
frequently deformed (M, 17.44+.22, o, 2.46+.16, CV, 14.15+.93). 
Plain agar (shredded agar only, 12 g. per liter)—The fungus grew 
rapidly, and in 6 days the colony was 35-45 mm. in diameter, but was 
thin and colorless, with but few scattered conidia, and only 1 to 3, 
or at the most 7 to 10, conidiophores per low-power field, except at 
growth-inhibition points, as at the edge of the dish or where two colonies 
approached each other, where the number of conidiophores rose to about 
12 per low-power field. The conidiophores bore only one or two conidia 
each. Conidiophores, conidia, and mycelium as well, were very faintly 
straw-colored, much paler than on more nutrient agar. No zonation 
occurred. No difference in rate or character of growth was observable in 
1.3% and 2.6% plain agar. 
Growth on plain agar, on corn-meal agars, and on various combinations 
of these nttrients—Corn-meal agar of various compositions was used, 
12 c.c. to each Petri dish. On 25% corn-meal agar (made of 3 parts plain 
agar plus 1 part ordinary corn-meal agar) the colony was much darker 
and denser than on plain agar; was zoned more strongly; and conidia were 
much more abundant, there being about 80 conidiophores per low-power 
field, each with one to five conidia. The mycelium was much darker 
than on plain agar. Colonies on 50% and 75% corn-meal agar showed 
no essential difference from the colony on 25% agar. On full corn-meal 
