16 NORTH AMERICAN FEVER TICK AND OTHER SPECIES. 
located toward one end and seems to be due to the excretion of- the 
embryo. In Margaropus annulatus it is very conspicuous and is a 
_certain indication of viability. 
The act of oviposition is most interesting. This process was 
referred to by Dr. Cooper Curtice.¢ An analogous operation in 
Ixodes ricinus has recently been carefully described and illustrated 
by Wheler,? and was earlier noted by Lewis. One of our asso- 
ciates, Mr. R. A. Cushman, has observed the operation. The follow- 
ing description is based upon his notes: 
When oviposition is about to take place the capitulum is bent 
downward toward the genital aperture. This exposes a delicate, 
viscid membrane between the capitulum and the scutum. ‘The 
membrane becomes distended and is projected out over the capitu- 
lum in two rounded lobes, practically covering it. This process is 
repeated several times before the egg is finally ejected, the mem- 
brane being extruded and retracted alternately while the capitulum 
is lowered and raised. Finally the white, membranous ovipositor is 
extended, turning inside out, until it Hiclitee the distended mem- 
brane. The capitulum is now completely hidden. As soon as the 
ovipositor and membrane have come in contact the former slowly 
recedes, leaving the egg adheri ing to and partially enveloped by the 
membrane. The egg remains in this position for a varying length of 
time. Then the membrane is withdrawn, rolling the egg along for a 
short distance on the dorsal surface of the capitulum. At the same 
time the capitulum is raised. Then the processes of distention and 
contraction of the membrane and lowering and raising of the capitu- 
lum are repeated several times, the egg being finally completely 
coated by the viscid substance from the membrane and being finally 
pushed back and deposited on the anterior edge of the scutum. 
Each egg is laid in this manner, the tick backing slowly away and 
leaving the mass of eggs in front of her. The actual time consumed 
by the tick in laying a single egg is about 30 seconds, while the 
removal of the egg and the resting period consume from one to sev- 
eral minutes, a much longer resting period being taken at intervals 
between lots of from 10 to 50 eggs. It has been impossible for us 
with the means at our command to demonstrate the ‘paired, race- 
mose glands” of the membranous sac referred to by Curtice. As far 
as we have been able to see, the substance with which the eggs are 
coated is secreted from numerous minute glands scattered over the 
surface. 
a Tex. Agr. Exp. Sta., Bul. 24, p. 242. 
b Journ. Agric. Sci., 1906, p. 405. 
¢ Proc. Roy. Micros. Soc., 1892. 
