ERADICATION OF THE ROCKY MOUNTAIN SPOTTED FEVER TICK. 5 
On the lambs, ticks were found attached in several different places : 
Some were in front of the ears, some in the wool on top of the neck, 
others in the wool on the top and sides of the shoulders, and one was 
attached, as stated before, on the chest. In no case were the ticks on 
lambs found attached on the hind quarters or beneath the body. 
The ticks referred to as crawling were no doubt those males and 
females which had recently gotten on the sheep, or perhaps they were 
males seeking females. Besides the females referred to in Table I as 
" engorged one-half or more," there were some other females which 
had fed slightly but had never become as much as one-half engorged. 
This division at one-half engorged is made because females less than 
about that size seldom lay eggs. Should ticks less than one-half full 
get rubbed off, it is extremely doubtful if they would ever deposit 
eggs. Just how many ticks were rubbed off or killed before complete 
engorgement it is impossible to say, but a few cases of this kind were 
observed. In all cases in which females are referred to " with males 
beneath," such pairs were in the correct position to effect fertilization. 
The " engorged females recovered from sheep," except one, were 
picked from the host when they had reached full or nearly full 
engorgement. 
It seems probable that the dead unfed ticks found in the wool were 
for the most part killed by the lanolin, although the heat of the wool 
may have been a factor. It was found in a number of cases that ticks 
died after attaching. This factor was indicated by a reddish spot on 
the skin near the place where the tick was found dead. The ticks, 
however, were usually found loose in the wool. Both living (at- 
tached) and dead ticks were found at times in the same fold. 
To show the location of the ticks recovered and the relation between 
shearing and the development of the ticks, certain data in Table I 
have been rearranged in Tables II and III. 
Table II. — Location of ticks recovered from sheep. 
Dead. 
Alive. 
Head 
31 
28 
30 
23 
3 
45 
Neck 
29 
Upper parts 
15 
Sides 

Underneath 
23 
i On the shoulder. . 2 Two on leg. 
Table III. — Relation between shearing and attachment of ticks. 
Lambs not sheared 
Sheep not sheared 
Sheep sheared (including ram) 
Dead 
females. 
Engorged 
females. 
