TEXAS FEVER. 
331 
(April 20), at which time the average per cent, was 33.5. The 
lowest average reading found since that time was 30.5 per cent., 
which occurred on the 113th and 120th days. 
Third inoculation .—On May 18, the I32d day, a third inoc¬ 
ulation was made. This consisted of 2 cc. of immune, defibri- 
nated blood given subcutaneously to Nos. 1, 2, 3 and 5. No. 4 
received 1 cc. of the same material. (No. 6 had died of black¬ 
leg 011 April 10th.) The reaction from this was very feeble. 
The highest morning temperatures noticed were : No. 1, May 
28th, 102 0 ; No. 2, May 20th and 23d, 103.3 0 ; No. 3, May 25th, 
103.4 0 ; No. 4, May 25th, 105.2 0 ; No. 5, May 28th, 103. 0 
It appears from this that No. 4 showed some reaction, but it 
was of short duration. The others may be regarded as a very 
feeble reaction, if any. The haematokrit readings do not indi¬ 
cate any appreciable blood destruction, so that we may regard 
the third injection as producing no effect, and assume that im¬ 
munity has been attained. These cattle were placed in the 
pasture April nth. It remains to be shown that they were ex¬ 
posed to infection. They were frequently examined for ticks. 
The cattle were infested with young ticks (B. bovis) on 
May 5th, May 6th and May 27th. During June and July they 
carried and matured a few fever ticks. It was not until August 
FIG. IO.—GRADE HEIFERS FROM BOONE COUNTY, MISSOURI, USED IN INOCU¬ 
LATION EXPERIMENTS AT THE TEXAS EXPERIMENT STATION. 
