New York AGRICULTURAL EXPERIMENT STATION. 129 
During the winter the dark discoloration gradually changes to 
a light gray and the areas become indefinite in outline and more 
difficult to locate. (Plate IX, Figs. 2-4.) In April they are 
found to be thickly studded with small black perithecia, the 
numerous asci of which each contain eight two-celled hyaline 
spores disposed in uniseriate or subbiseriate fashion. (Plates IX 
and X.) By May 1 the entire lower portion of many canes is 
light gray in color and thickly covered with the perithecia. Still 
there is no discoloration of the wood underneath and no other 
indication of injury to the canes. 
Some canes affected in this way were marked and watched for 
about three months to ascertain if they became affected with cane 
blight later. On May 2, 1902, ten affected canes of the variety 
Carleton were selected and labeled. Care was taken to select 
canes en which the affected areas were well defined. From each, 
a bit of bark was taken and examined with the microscope to 
make sure that the fungus present on the gray areas (formerly 
bluish-black) was the pyrenomycete above mentioned. On August 
7, 1902, the ten canes were cut and carefully examined. All were 
either dead or dying, but in every case the cause was traced to a 
Coniothyrium infection at some other point on the cane, usually 
higher up. In two cases the Coniothyriwm had made its attack 
just above the gray area and here the Coniothyriwm pycnidia 
were intermingled with the perithecia of the pyrenomycete. It 
was plain that the gray areas were not the seat of the trouble 
and that the pyrenomycete was not succeeded by Coniothyrium. 
This view is supported by numerous other observations and we 
think that it may be accepted as an established fact that the 
discolored areas, which are bluish-black or brown on new canes 
and light gray and inhabited by the pyrenomycete the following 
spring, do not represent the early stage of cane blight; also, 
that this pyrenomycete and Coniothyrium are two entirely dis: 
tinct fungi. In April and May it is sometimes difficult to dis- 
tinguish, without microscopic examination, Coniothyrium infec- 
tions from the gray areas inhabited by the pyrenomycete. The 
color of the bark is similar, but if the Coniothyrium has expelled 
its spores it may be recognized by the smoke-colored smuttiness 
9 
