92 THE COMMON TICK. 
the blood of diseased cattle, conveys the disease-germs to its. 
young, whichearryit to othercattleinvaded by them. In the 
region south of the two rivers mentioned above, the disease 
is seldom fatal to the native stock, in the blood of which it 
always seems to exist; at least it can be artificially inocu- 
lated from apparently healthy southern cattle into healthy 
northern stock. If native cattle are brought from the 
northera regions into the permanently infected region they 
are almost certain to contract the disease if permitted to run 
at large. Younger cattle may be acclimated and not catch 
the disease in its dangerous form. Ifsouthern cattle, carry- 
ing with them such ticks, are sent north, the latter drop off 
when mature and deposit eggs upon the soil of the pastures, 
stables and yards; the young ticks, hatching in eighteen to 
twenty-four days, thus reach other stock and as they carry 
with them the microbe causing the disease and as they are 
not slow to bite, they convey this disease, which in from two 
to three weeks developes into Texas fever. All these interest- 
ing facts were discovered by the careful investigations made 
by the U. S. Department of Agriculture. 
REMEDIES.—Though we do not find this dangerous tick 
in Minnesota it is well to know the proper treatment, 
especially as this is equally effective against the ticks found 
here. Pine tar, one gallon; kerosene, fish-oil or crude car- 
bolic acid, one quart; and powdered sulphur, two pounds, 
should be thoroughly mixed. This makes an excellent salve 
for sores, and will also protect animals against flies; as apro- 
tection fish-oil is better than either kerosene or carbolic acid. 
The salve should be thoroughly rubbed in, and this operation 
should be repeated from time to time. 
THE COMMON TICK. 
(Dermacentor americanus L.). 
This tick is the only one that is common in our state,and 
very common in: some localities. It is found especially 
numerous upon hunting-dogs. As very little seemed to be 
known about the life-history of this tick some full-grown 
specimens, swollen with eggs, were put in a moist-chamber. 
They were not slow in depositing immense numbers of eggs, 
