eres! INSECTS AFFECTING DOMESTIC ANIMALS. 
An extra provision for this purpose consists of a double plate having 
fine transverse ridges in the basal joint of the tarsus. This structure 
appears to have been first described by Professor Harker (Agricultural 
Students’ Gazette, Vol. I, p. 162). The abdomen differs greatly in form 
and size, according to the degree of distention, which accounts for the 
discrepancies in the different figures of this species. It may be called 
flask-shaped and more or less flattened according to the amount of 
matter contained in it. There is a row of horny tubercles along each 
side and a row of chitinous plates along each side of the upper surface 
of the abdomen. ‘The spiracles are located in the tubercles at the 
sides, and there is one to each of the last six segments, omitting the 
terminal one. In color there is some variation, as would be surmised 
from a comparison of descriptions by different authors. The general 
color of the head and thorax is a light brown approaching to yellow- 
ish, with touches of bright chestnut on the head and legs and margins 
of the 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 noticeable in preserved 
specimens, besides its color depends evidently in large degree upon 
its contents. Denny says “grayish-white or ochraceous gray,” which 
would apply well to preserved specimens, but his 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 tubercles 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. Figure 100, e represents one of the eggs, showing its attach- 
inent to the hair and the distance from the root of the hair in the speci- 
men drawn. The adhesive substance evidently invests the egg during 
Oviposition and is touched 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-oval, tapering 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 con- 
nection is to be seen between different points, but focusing a little below 
the surface brings into view what appear to be minute threads or chan- 
nels running from point to point and giving a reticulate appearance to 
the eggshell. The points can not correspond to the circular bodies rep- 
resented in Denny’s figure (E, Pl. XX V, 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 
