LIFE HISTORY OF CATTLE TICK. 23 
PERCENTAGE OF EGGS HATCHING. 
To determine the exact percentage of eggs hatching is a rather 
difficult matter for the reason that manipulation in counting inter- 
feres greatly with their viability. In June, July, and August, 1906, 
a number of observations were made showing the percentage of 
viable eges in different lots from 30 to 90. In these cases the eggs 
were counted, and it is likely that the percentage hatching under 
natural conditions is considerably higher than that indicated. The 
examination of masses of eggshells where hatching has taken place 
normally reveals few unhatched eggs. 
Messrs. Newell and Dougherty* have recorded a percentage of 
hatching during the months of April, May, June, July, August, and 
September of from 61.6 to 92. These experiments were performed 
at Baton Rouge, La., under conditions which approached the natural 
ones very closely, although the eggs were counted as in our experiments. 
LARVAL OR SEED-TICK STAGE. 
The larval tick isa minute 6-legged creature without distinct genital 
opening, and with indistinct stigmata between the second and _ third 
pairs of coxe. As Salmon and Stiles state, larval ticks frequently show 
indications, at least, of stigmata between the first and second pairs 
of coxe, and behind the posterior coxz in addition to those between 
the second and third pairs. Only the pair first mentioned seem to 
be functional. The color of the larva at first is whitish but soon 
becomes dark brownish. 
NONPARASITIC PERIOD. 
‘For a few hours the larva remains about the shell from which it has 
just emerged, but later makes its way upward on the first blade of 
grass, stick, post, or other support that presents itself. Professor 
Morgan informs us that he has seen seed ticks on the tips of sugar 
cane about 8 feet from the ground. By placing a pole in the vicinity 
of millions of seed ticks we have observed them to reach a height of 
about 6 feet in a surprisingly short time; but the tendency is strongly 
to remain not more than about 4 feet from the ground. In the absence 
of some vertical object the seed ticks do not seem to scatter to any 
great extent, but collect on the highest immediate point, even if it 
is only a small clod or stone. 
On whatever support the young ticks happen to be, they collect 
in masses often nearly an inch in diameter. (See Pl. I, fig. 2.) Here 
they remain for weeks or months awaiting a host. The front legs, 
which combine the functions of antennz and legs in the insects 
@La. Crop Pest Comm., circ. 10, p. 24. 
