1898 | THE DEVELOPMENT OF SOME ANTHRACNOSES 89 
first. With successive generations, obtained by making trans- 
fers of cultures, the fungus became gradually adapted to artificial 
conditions, and vigorous growth was obtained in potato-agar. 
A normal type of germination takes place; one or two germ 
tubes arise from near the ends of the conidium, making their 
first appearance within six or twelve hours after the sowing is 
made. Twenty-four hours after sowing the conidia have usually 
all germinated. 
The contents of the conidium become coarsely granular, 
and a clear space at the point of origin of the germ tube is 
seen as its contents pass into the tubes. The mycelium becomes 
coarsely granular or vacuolate, and branches in an irregular 
monopodial fashion. As the colonies exhaust the nutrient 
medium large hyaline vesicles appear as offshoots of the myce- 
lium, or short branches of the mycelium become very much 
enlarged at the tips. The colonies make their first macroscopic 
appearance as small, irregularly stellate bodies; as they become 
older, the mycelial growth is nearly uniform, radiating from a 
small, dense central point. The conidia are first formed most 
abundantly at the center of the colony, where a pink acervulus 
appears. When the colony attains the age of five or seven 
days, the acervuli are formed irregularly over the central portion 
of the colony, the marginal mycelium keeping some distance in 
advance of the fruiting portion. The setz are produced quite 
abundantly on the acervuli; in fact, the characters of Colleto- 
trichum are often more distinctly manifested in artificial cultures 
than in a natural state. At the center of the colony a compact, 
reddish-brown stroma is formed, which does not spread far over 
the colony ; beyond this stroma the colony acquires uniformly 
a buff or salmon tint. Faint concentric markings are sometimes 
seen in the colony. ; 
Transfers to bean stems give rise at the point of inoculation 
to a spreading, grayish mycelium which covers the stems and 
the infusion. About three days after sowing the pustules appear 
in circular, elevated masses of a dull pink hue. As the culture 
becomes older they become surrounded by a stroma which gives 
