LICE AFFECTING DOMESTIC ANIMALS. 
201 
thorax, also touches of dark brown on these parts, more par¬ 
ticularly on the dorsal portion of the thorax. The abdomen 
in fresh specimens has a general bluish aspect, not so notice¬ 
able in preserved specimens, besides its color depends evi¬ 
dently in large degree upon its contents. Denny says “ gray¬ 
ish-white or ochraceous gray,” which would apply well to pre¬ 
served specimens, but this plate shows it a blue-gray. Harker 
says brownish gray. It appears to us that the term used by 
Mr. Tenney, blue slate-colored, comes quite as near describing 
the average appearance as any that we have seen. The tu¬ 
bercles at the side of the abdomen and the chitinous plates 
are chestnut-colored, while the most* of the upper surface of 
the terminal segment in the female and the ventral stripe in 
the male are black. 
The females deposit their eggs on the hair, attaching them 
very near the skin. Fig. i e represents one of the eggs, 
showing its attachment to the hair and the distance from the 
root of the hair in the specimen drawn. The adhesive sub¬ 
stance evidently invests the egg during oviposition and is 
attached to the hair, the egg then slightly drawn along so 
as to leave the glue-like mass to form a firm union around 
the hair and to the egg. The egg is elongate-shaped, taper¬ 
ing at the lower end, and having a cap-like covering at the 
upper end. The surface is set with very minute points just 
visible under an inch objective, but showing clearly with a 
power of 300 diameters. At the surface no connection is to 
be seen between different points, but focusing a little below 
the surface brings into view what appear to be minute threads 
or channels running from point to point and giving a reticu¬ 
late appearance to the eggshell. The points cannot corres¬ 
pond to the circular bodies represented in Denny’s figure (E, 
Plate xxv, Monog. Anop. Brit.) which have much more the 
appearance of protoplasmic granules of the egg contents. 
The shape of the egg in his figure is also entirely different 
from that of the specimen from which our figure is drawn. 
The young louse escapes from the outer or unattached 
end, whether by pushing off the cap-like portion or simply 
pushing through this portion which appears to be thinner 
