47 
of the field. It would also seem, in regard to the second of the above- 
named points, that the prevention of seepage by short-rooted annual 
plants or even alfalfa would be slight and would be more than repaid 
by the profits on the grain or hay harvested along the ditch. However, 
it is the practice, with only very rarely an exception, to allow these 
spaces to grow up to weeds. In these extremely damp places it is not 
to be wondered at that species of locusts with such habits as Jelanoplus 
bivittatus become exceedingly abundant and troublesome. In fact, these 
strips are thestarting point of sucha number of locuststhat in this region 
the total acreage is much affected. They hatch in the spring and spread 
over the fields, then when the grain is cut, are driven back to the sides 
of the ditches, from which place they spread to deposit their eggs in the 
fall. It would be the simplest of matters to exterminate them, even 
though the practice of leaving strips along the sides of the ditches were 
not given up, by the thorough aid persistent use of *‘dozers” after the 
grain had been cut from the fields. In short, all the locusts in the 
country are driven at this time to the sides of the irrigating ditches, 
and no doubt at that time a process of driving by means of beating of 
the locusts, which is very easily accomplished, from the inside of the 
fences to the outside and the drawing of * dozers” along the roadsides 
with an analogous process applied to the ditches would result in the 
destruction of all of them. Forthis purpose a modified *-dozer” drawn 
by a horse attached to one side would be of best avail. The expense 
compared to the present annual loss would be very slight, and should 
be borne by the counties in the infested areas, If this is not done dam- 
age will result in the future just as certainly as the seasons recur as 
loug as the present method, or lack of method, is in vogue. 
One of the most valuable observations made in the territory most 
infested was the presence of immense flocks of Brewer's blackbird 
(Scolecophagus cyanocephalus Wagl.) hovering along the roads and 
destroying immense numbers of the locusts. Several birds obtained 
from a flock in the vicinity of Fort Collins had their stomaclis crammed 
with from 50 to 50 specimens of these insects. The grasshopper fun: 
gus disease, Hmpusa grylli Fres., and Tachinid parasites were most 
numerous in the vicinity of Greeley. However, these attacks are rather 
local, and they do not seem to affect the local situation, especially since 
the flies do not appear until the locusts have done most of the damage 
which they are capable of doing. 
In the western part of Colorado an unexpected and dangerous find 
was made in the presence of Acridium shoshone Thos. in the Grand 
Valley above Grand Junction. This species has not been tound in this 
region before, though it has been known to infest adjacent parts of 
Utah. It was only seen in the Grand Valley bottom near DeBeque, 
and was feeding upon willow. It was present nowhere in injurious 
numbers and was not discovered upon fruit trees. It is an arboreal 
species, and under the conditions, which appear to be very favorable for 
