648 ; LAauRA FLORENCE 
Neither feces nor blood was ejected from the anus, but a drop of hyaline 
fluid escaped from the sexual orifice almost simultaneously with the pointed 
end of an egg. After a few seconds the louse moved away, leaving the 
egg attached to a hair on the arm. The position of the gonopods could 
not be seen, but the posterior lobes of the ninth abdominal segment 
surrounded the hair on which the egg was laid. According to Sikora 
(1915:536), who has described the act of egg-laying on a bristle by a hog 
louse in captivity in a vial, the insect remained motionless for almost 
ten minutes after the first appearance of the egg, and then moved off 
leaving the egg attached to the bristle. Watts (1918:9) says, “‘ The entire 
operation requires but a few seconds, so that one seldom sees a female 
lay an egg unless watching closely for some time.’ In the ovaries the 
eggs are oriented according to Hallez’ law, and, when laid, the ventral 
surface is attached to the bristle. The cement surrounds the bristle 
but does not appear to surround the egg, which is attached to the bristle 
between its transverse median line and its posterior end. One or more 
eggs may be laid on the same bristle, not always pointing in the same 
direction. After attachment we have always found them immovable, 
but Watts (1918:9) states that he has found they can be slipped along 
the hairs and are often pulled away from the body by the rubbing of the 
animal. This, however, does not agree with his earlier statement on the 
same page, that “‘ each egg is glued to the base of a hair and is laid so 
that the smaller end practically touches the skin of the host, which keeps 
the egg warm until it hatches, several days later ’’; and, since the diameter 
of the bristle diminishes toward the tip, the cement ring large enough to | 
surround the base of the bristle would tend to slip off, carrying the egg with | 
it, thus causing an excessive mortality not provided for by overproduction. 
In captivity the eggs are laid on bristles or threads of gauze, and the 
number laid daily appears to depend on the opportunity to feed, as the 
following table shows: 
festnt a Sunigufs iain ba hee Authority 
Job eta SePAUN. up NIEMAN MeN AUK CL Des Sikora 
Continuous): REG cee ene un Hee AS NO nN ae Sea Sikora 
Continuousor days. yaene By ae cane Claassen? 
BD yO 2 pes eg UCL SI SNR oe Ae ND (eh), coe a ee Florence 
3 Unpublished data kindly communicated to the writer by Professor P. W. Claassen, of the Department | 
of Entomology, Cornell University. 
