379 
from the receptacle at one or more points and thus opens the gall. 
The tissue of the gall is quite hard as compared with that of the 
hypertrophied fruits caused by £. Pruni and related species. The 
hollow interior is comparatively smooth, and in the apex of this 
several of the larvz of the cecidomid are bunched. 
The fungus appears only to attack a portion of the surface. 
These portions are then still more swollen and cause the gall 
to be quite strongly curved. The asci are cylindrical or rarely 
clavate. They are 30-40 long by 6-10 # in diameter. The 
stalk-cells are very broad and rounded below, being 6-10 / high 
by 10-15 “ in diameter. 
Further study is needed to determine just the relation which 
the cecidomid bears to the fungus. At the present writing I do 
not think that the fungus occurs on all of the fruits which are de- ; 
formed by the insect. 
Besides these prunicolous species of Exoascez two others 
Worthy of note have been collected by myself in the Southern 
States. One of these proves to be undescribed. 
Exoascus AUSTRALIS n. sp. 
This was collected at Auburn, Ala., April 30, 1892, on the 
leaves of Carpinus Americana Michx. It attacks only the leaves 
and does not deform “ Witches’ Brooms,” as does Exoascus Car- 
pint Rostrup, upon Carpinus Betulus in Europe. It is in other re- 
Spects very different, . 
_ Usually nearly the entire leaf is affected and strongly arched 
upward, giving it a rude, boat-shaped appearance. There are also 
Separate archings between the larger lateral veins which thus throw 
the surface into a series of strong folds. The upper surface of the 
leaf is bright red until it begins to die, when it turns brown, then 
black, then falls away. i 
The asci are borne only upon the upper surface, in so faras I 
have observed. They stand closely crowded together They are 
Mostly cylindrical, and 50 “long, but sometimes vary from 30- 
“ long. The usual diameter is from 7-8 “, but sometimes 
they become even 10 “, where ‘they are not very much 
crowded. The ends are truncate, They lack a_ stalk-cell, 
but frequently the base is more or less abruptly narrowed into a 
