8 EXTERMINATING THE TEXAS-FEVER TICK. 
Kgg laying (see fig. 2) begins during the spring, summer, and fall 
miontian in from two to twenty days, and during the winter months 
in thirteen to ninety-eight days. The eggs are small, elliptical- 
shaped bodies, at first of a light amber hie i eos to a dark 
brown, and are about one-fiftieth of an eich in length. i the eggs 
are laid they are coated with a sticky secretion which causes them 
to adhere in clusters and no doubt serves the purpose of keeping them 
from drying out. During egg laying the mother tick gradually 
shrinks in size and finally is reduced to about one-third or one-fourth 
her original size. Egg laying is greatly influenced by temperature, 
being retarded or even arrested by low temperatures. It is com- 
pleted in from four days in the summer to one hundred and fifty-one 
days beginning in the fall. During this time the tick may deposit 
from a few hundred to more than 5,000 eggs. After egg laying is 
completed the mother tick has fulfilled her purpose al dies in the 
course of a few days. 
After a time, ranging from nineteen days in the summer to one 
hundred and sence sidn: days during the fall and winter, the eggs 
begin to hatch. From each egg issues a small, oval, six-legged larva 
or seed tick (fig. 3), at first amber colored; later changing to a rich 
brown. The seed tick, after crawling slowly over and about the shell 
from which it has emerged, usually remains more or less quiescent 
for several days, after which it shows great activity, especially if the 
weather is warm, and ascends the nearest vegetation, such as grass, 
other herbs, and even shrubs. 
Since each female lays an enormous mass of eggs at one spot, 
thousands of larvee will appear in the course of time at the same place 
and will ascend the near-by vegetation and collect on the leaves. 
This instinct of the seed ticks to climb upward is a very important 
adaptation to increase their chances of reaching a host. If the vege- 
tation upon which they rest is disturbed, they become very active 
and extend their long front legs upward in a divergent position, 
waving them violently in an attempt to seize hold of a host. 
The seed tick during its life on the pasture takes no food and conse- 
quently does not increase in size, and unless it reaches a host to take 
up the parasitic portion of its development, it dies of starvation. 
The endurance of seed ticks is very great, however, as they have been 
found to live nearly eight months during the colder part of the year. 
DEVELOPMENT ON CATTLE. 
The parasitic phase of development begins when the larve or 
seed ticks reach a favorable host, such as a cow. They crawl up 
over the hair of the host and commonly attach themselves to the 
skin of the escutcheon, the inside of the thighs and flanks, and to the 
dewlap. They at once begin to draw blood and soon increase in 
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