14 NORTH AMERICAN FEVER TICK AND OTHER SPECIES. 
PERIOD PREVIOUS TO OVIPOSITION. 
The cattle tick, like other species, passes through a distinct period 
between the time of dropping from the host and the beginning of ovi- 
position. When the tick drops, the eggs are not ready to be depos- 
ited, but must pass from the ovary through the oviduct. (See fig. 1.) 
Thus there is a definite physiological basis for a period which has a 
very practical bearing on plans of eradication that depend upon a 
a 
Fig. 1.—Genital apparatus of Margaropus microplus: a, 
Position of eggs at time of dropping of tick from host; 
b, position of eggs when oviposition begins. Highly 
magnified (redrawn from Lahille). 
knowledge of the exact time 
to be allowed in removing 
cattle from one inclosure to 
another. lLahille has used 
the term “prootoquie”’ for 
this period, but we shall refer 
to it merely as the preovipo- 
sition period. 
_As will be seen from Table 
I the preoviposition period 
ranges from 2 to 40 days, 
depending upon tempera- 
ture. In the summer it 
averages between 3 and 4 
days, and in winter over 20 
days. 
It niight be supposed that 
the data in the table referred 
to show a preoviposition pe- 
riod longer than normal on 
account of the removal of 
the ticks artificially. How- 
ever, only ticks about to drop 
were selected, and repeated 
tests with ticks actually dropped showed that the method followed 
gives the natural preoviposition period. 
OVIPOSITION PERIOD. 
As will be seen from Table I, the period occupied in oviposition 
ranges from 6 to 70 days, depending upon the temperature. In the 
summer it averages 10 or 11 days, while in the winter it is two or 
three times as long. 
