204 
HERBERT OSBORN. 
is longer than wide, and has a distinctly showing spiracle 
above the second pair of legs ; the abdomen is elongate, with¬ 
out chitinous plates and devoid of any tubercles along the 
sides; the terminal segment is also devoid of black horny 
band; the brush-like organ on the under side of the abdomen 
(see Fig. 3) is slender, while the terminal segment is set with 
numerous rather long hairs. 
In all of these points it will be observed there is a distinct 
difference from eurysternus. The brush-like organ on under 
surface of the abdomen, common to females of related species 
and which is wanting in young of all species, must be taken as 
distinct evidence of the maturity of the specimens. If, how¬ 
ever, there were any doubt on this point, a study of the young 
of eurysternus gives equally conclusive testimony. In the very 
youngest eurysternus we have seen that the chitinous tuber, 
cles along the sides of the abdomen inclosing the spiracles 
are distinctly to be seen, while the head, though longer pro¬ 
portionally than in adults, is by no means equal in length to 
that of adult vituli . A young vituli found, it is true, associ¬ 
ated with eurysternus shows this elongation of the head still 
more markedly. In color there is little difference in the two 
forms, this species having rather duller colors upon the head 
and thorax. The abdomen of young specimens, when full of 
blood, appears dark red, but the bluish-gray hue is more 
prominent in adults. The eggs of this species have not been 
described, and we have not had the good fortune to discover 
them. The young are even more slender than the adults. 
The remedies that are available for the preceding species 
will prove effectual for this, and it is evidently less difficult to 
subjugate than that form. 
The Hog-Louse. (Plate 1 , Fig. 5.) 
Hoematopinus urius , Nitzsch. 
Occasionally this species appears in formidable numbers, 
since we often hear of swine badly affected with lice, and nc 
other species is known to attack this animal. 
Giebel credits this species to Moufet, citing the Theatrum 
Insector, (1634, 266), while Piaget states that it is cited by 
