CHROMOGENIC FUNGI WHICH DISCOLOR Woop. 63 
s 
conidia in their descriptions is very limited indeed, only 
two being noted, and where such descriptions have been 
given, no mention is made of the connection between the 
conidial and the perfect or perithecial stages as being 
established by cultural methods. For instance, Ceratos- 
tomellaalbocoronata (Ellis) Sacc. has a conidial stage where 
the conidia are from 2- to 3-septate, and of abnormally 
large size. So far as our investigation has proceeded, all 
species of Ceratostomella have colorless conidia, that are 
one-celled and of about the same measurements as the 
‘ascospores. The presence of asci in the perithecia has 
been the most difficult point to prove. Cultures must be 
taken at the stage just preceding full maturity of the ascus, 
else it apparently dissolves and frees the ascospores at ma- 
turity, allowing their free ejection through the long, nar- 
rew beak of the perithecium, but destroying the evidence 
of the presence of a sac. In an examination of the ejected 
ascospores they are frequently found adhering to each 
other in fours, side by side, in the same position they 
occupied in the ascus. 
The conidial stage of Ceratostomeiia is very important, 
owing to the immense number of conidia borne on the 
mycelium in its earlier growth. These are readily dissem- 
inated by the wind and are probably carried by insects 
which penetrate the wood and bark of trees, like most of 
the ambrosia and bark beetles. At the stage in which the 
conidia form a mucilaginous mass, they adhere readily to 
any insect that may pass over them. In the laboratory a 
number of species of mites which feed on fungi carried 
spores on their bodies from a colony in an agar plate to a 
sterile portion of the surface of the medium and started 
new colonies of the fungus. Bark beetles were placed in 
a dish with the conidial stage of Ceratostomella, and after 
allowing them to remain a short time were transferred to 
sterile agar plates which were inoculated with spores 
from the insects. It is probable that some species of in- 
