418 CONNECTICUT EXPERIMENT STATION REPORT, IQI2. 
Besides these, there is a somewhat similar appearing fungus 
recently: described, by H. & P. Sydow (Ann. Myc. 10, p. 82) 
on Quercus from Colorado, as Calopactis singularis. It is a 
semi-parasitic species, apparently, whose generic position is some- 
what doubtful, as the asco-stage has not been found. It has 
been known in this country for some time, and by some botanists 
has been placed under Endothia gyrosa, since the fruiting pus- 
tules and the Cytospora spores of the two are very similar. 
However, the fruiting pustules are larger, deeper crimson in 
color, and in maturity more powdery. We have it in culture 
from a specimen recently sent by Bethel from Colorado, and 
while it grows something like E. gyrosa, it does not form any 
distinct conidial fruiting pustules on media tried so far, and in 
manner of growth and color of mycelium resembles more nearly 
the cultures of E. radicalis, 
Of the species mentioned, we need to consider in connection 
with the blight fungus only Endothia gyrosa, already discussed 
somewhat, and’ Endothia radicalis, since these three in their 
Cytospora stage are so similar in appearance that they cannot 
be distinguished by the naked eye, and all have at least the oak 
as a common host. As £. radicalis is most sharply set off from 
the other two, we will discuss it first. 
Endothia radicalis. While the fruiting pustules of this species 
are not different from the other two, when we examine the asco- 
stage under the microscope it is very easily distinguished by 
the much narrower spores. These ascospores vary from linear | 
to linear-oblong, are occasionally slightly curved, are apparently 
single-celled, though possibly they may in some cases develop 
an indistinct septum, and are 6-10 p, rarely 12 p, long by 
1-2 » wide. We have never seen spores which grade into those 
of the other two species described here, so it is apparently quite 
a distinct species. See Plate XXVIII a, d. 
It seems to be largely southern, having been found in its 
asco-stage in Louisiana, Mississippi, Georgia, Alabama, Florida 
and North and South Carolina. However, there are specimens 
in various herbaria from much further north, showing only the 
conidial stage, that apparently belong to this species. One speci- 
men found in Connecticut has been under observation on roots 
of an oak tree for over a year, and though in a vigorous grow- 
ing condition, has made no attempt to form the asco-stage. 
