232 
Bionomics of Pediciiliiis 
been fastened to two or more hairs at the angles of crossing. Nine eggs 
had been laid on the gauze cover of the box; only four eggs had been 
attached to the single hairs, while 21 (60 %) of the eggs were cemented 
to two or more of the hairs, the $$ having apparently searched for 
positions where the hairs crossed or ran parallel to each other so as to 
avoid attachment to single hairs. 
Several and dd of P. capitis were treated similarly, in this box— 
36 eggs were laid, all of them on hairs; 28 were attached to a single 
hair only; six had attachment to two and two to three hairs. A marked 
difference was observable, also, in the selection of position for attachment 
in the case of the eggs having attachment to more than one hair. In 
everv case the hairs chosen not only ran parallel for more than the 
length of the egg, but in most cases they were side by side. The parallel 
hairs affected by P. humanus were separated from each other by a well 
marked space, while in most cases hairs crossing each other at a wide 
angle had been chosen. 
P. humanus $$ in most cases exhibited what may be roughly called 
a homing instinct; that is to say they returned again and again to the 
same spot to lay their eggs. As this habit made counting difficult. 
