560 KUNKEL: ORANGE RUSTS OF RUBUS 
If there are, then, two orange rusts on the blackberries of the 
United States it would seem highly interesting and important to 
study them side by side in order to determine whether in addition 
to the difference in the way their aecidiospores germinate there 
are to be found morphological differences between the two 
Caeomas. The object of this paper is to bring the evidence 
which shows that we have two orange rusts on the American 
blackberries and to give a brief comparison of the two forms which 
have previously been confused and supposed to be one and the 
same rust. 
OBSERVATIONS 
It was in the hope of obtaining material for testing Fischer’s 
assumption that the writer, at the suggestion of and in company 
with Professor R. A. Harper, made a trip to the White Mountains 
of New Hampshire. Here in the vicinity of the village of Glen 
the writer had on two previous occasions marked spots where the 
wild blackberry plants were infected with Puccinia Peckiana. 
On visiting these spots June 28, 1916, we found the plants well in- 
fected with a Caeoma. So far as we were able to determine 
macroscopically this Caeoma had all the characteristics of Caeoma 
nitens. The young infected shoots were chlorotic and somewhat 
taller than the normal ones. Many of the infected leaves were 
more or less deformed just as may be observed in the case of 
plants diseased with Caeoma nitens. Spermogonia were present 
in great abundance. Several infected plants and a considerable 
number of well-infected leaves were taken to New York City. 
The plants were put into flower pots and placed in a greenhouse, 
the purpose being to find out whether they would produce teleuto- 
spores later in the summer. 
In order to test the germination of the aecidiospores they 
were dusted over the surface of tap water in Petridishes. Twenty- 
one cultures were thus made and incubated at room temperature 
(about 25° C.). In twenty-four hours most of the spores had 
germinated. They produced long germ tubes having all the 
characteristics of aecidiospore germ tubes. No cross walls were 
to be found and no branches that might be taken for elongated 
sterigmata. The twenty-one cultures of germinating aecidio-— 
spores were carefully observed under the microscope and in only 
