36 NORTH AMERICAN FEVER TICK AND OTHER SPECIES. 
many cases from 5,000 to 10,000 seed ticks were placed on the animal, 
but only from 1 to 20 adults ever developed. Prof. H. A. Morgan 
made the suggestion, based upon the observations made by him in 
Louisiana, that the ration the steer was receiving was responsible for 
this remarkably small proportion developing. At his suggestion we 
changed the ration. The steer had been receiving daily 4.76 pounds 
of corn chops and 5 pounds of prairie hay. The inspection tag on the 
chops guaranteed not less than 9 per cent protein crude and not less 
than 4 per cent fat crude. At Professor Morgan’s suggestion the 
corn chops were eliminated. Immediately a much larger percentage 
of seed ticks developed to adults on the animal, although his general 
condition did not seem to have been changed materially. While 
before a dozen adults from many thousand seed ticks was the maxi- 
mum, after the change in the ration hundreds developed from no 
larger numbers of seed ticks applied. 
ENEMIES OF TICKS. 
At one time it was supposed that sowbugs may sometimes be 
important factors in the destruction of tick eggs. A number of 
observations have shown that the greatly preferred food of these 
isopods is vegetation either live or decayed. In laboratory experi- 
ments Armadillidium vulgare was found to feed on dead ticks and 
also to devour the eggs whenever no other food was provided. Thirty- 
eight sowbugs, furnished with 897 tick eggs, consumed 366 at the rate 
of 3 eggs per day each. In another case two sowbugs devoured 159 
tick eggs at the rate of 15 each per day. These results hardly seem to 
substantiate the impression that sowbugs may be of considerable 
economic importance. It should be emphasized that the experiments 
referred to were conducted in the laboratory, and the sowbugs were 
deprived of other food. Under natural-conditions the results might 
have been quite different. 
The little “‘fire-ant”’ (Solenopsis geminata Fab.), which has recently 
been found to be acquiring a special taste for the boll weevil, undoubt- 
edly destroys many engorged ticks that have dropped to the ground. 
Experiments performed by placing ticks in the immediate vicinity of 
nests of this ant show that under such circumstances they must 
invariably be killed. The nests of this ant are found throughout the 
pastures in the South, and the total of the work done by them must 
be considerable. 
A number of dipterous larve have been found feeding upon tick 
eggs and an undetermined species of Phoridz has been bred. 
At one time we were inclined to believe that a chalcidoid parasite 
of the cattle tick had been reared. Early in 1906 such a parasite 
was found in a pill box with the remains of an engorged tick placed 
there the fall before. Upon sending the specimen to Dr. L. O. How- 
