PARASITES OF ANIMALS. 41 
The Cattle-louse (Hematopinus vituli Denny). Figure 33- 
In the genus Hematopinus, which includes a large number 
of species, the head is obtuse or truncated in front, the middle 
segments of the abdomen well separated, and the posterior 
legs much the longest. The eyes are very minute. They are 
all small and some are minute species. 
Figure 33. 
H. vitult is brownish, with a pale 
abdomen, the abdominal segments 
bearing lateral chitinous pieces, in 
which the spiracles are situated. The 
head is elongated with a constriction 
behind the antenne. It is about y, 
of an inch in length, ora little more. 
It is parasitic both on cattle and horses, 
and sometimes becomes very abun- 
dant. 
Another species (CH. eurysternus 
Y/ Denny), also infests both cattle and 
horses. In this the head, thorax, and fect are horn-colored. 
The thorax is very broad. The length is abouty, of ah 
inch. 
The Hog-louse (Hematopinus suis Leach). Figure 34. 
Figure 34. This species is brown, with a white 
abdomen. The spiracles are placed in 
blackish, horny plates along each 
side of the abdomen. Length $ of an 
inch. ; 
H. stenopsis infests the goat. It is 
a horn-colored species, with a long oval 
hairy abdomen. 
H. asini Denny is parasitic on the 
— ass. 
H. piliferus Denny lives upon the dog. It is uniformly 
horn-colored. The body is slender and covered with pale 
hairs. Length yy of an inch. 
Figure 33.—Cattle-louse (Hematopinus vitult Denny), much enlarged. From 
American Naturalist. 
Figure 34.—Hog-louse (Bigsuis Leach), maghenlarged. From Cuvier. 
6 
