142 HORSE AND CATTLE FLIES. 
far back as the year 1815 it appears to have been known of as present 
by Bracy Clark, but looked on by him as the male of our H. bovis, and 
also then and since under doubtful synonyms. 
As, however, this fly and its maggot are almost indistinguishable 
from our well-known kind, excepting by skilled and careful investi- 
gators, and also its method of damaye to hides, and its history in the 
later parts of its life, are similar, it appeared to me superfluous to enter 
on the subject. 
Now, however, circumstances are different. Since the year 1892, 
in which a most carefully detailed paper of observations of what the 
whole life-history of this H. lineata was considered to be, by skilled 
official investigation and record of results on the part of the U.S.A. 
Department of Agriculture, was published in their official ‘ Bulletin,’ a 
wish has been expressed to me from the late entomologist of the U.S. 
Department, Prof. Riley, and also from his able successor in office Mr. 
L. O. Howard, that I would endeavour to find how far our British 
warble attacks coincided with those of the States. Therefore, besides 
my own endeavours in the matter, I give first, and mainly from the 
paper referred to, some of the chief points of the infestation, to 
facilitate comparison of the habits of the two species.* 
This H. lineata, Villers, of Kurope and America, is slightly smaller 
than our H. bovis, from half a line to a line less in length, besides 
being less in bulk, and of a lighter make. One marked difference in 
colouring is that the black upper portion of the fore body, and the band 
across the middle of the abdomen above, are of a brown-black, not of 
the beautiful velvety black of our bovis. Also the front, sides, and 
back of the head, sides of the fore body, a band across the base of the 
scutelium, and the basal segments of the abdomen, are covered with 
long yellowish-white, almost white, hairs; the terminal segment of the 
abdomen is reddish-orange. The fore part of the fore body (thorax) is 
dirty white, and along the top are four prominent raised lines. The 
figure of H. bovis, p. 184, will give, with differences noted, a fair idea 
of the appearance both of the fly and maggot of H. lineata. 
Of this (lineata) the maggot is stated to be more slender in shape, 
and more rugose than that of our bovis, and, when it has escaped from 
the warble, of a greyish-brown colour, striped with whitish-grey, and 
not of the browner tint, nor of the thick rounder shape of the larva of 
our Ox Warble Fly. Also it is shown in diagrams after Brauer (p. 311 
of work above referred to) that in H. lineata the terminal segment only 
of its larva is entirely bare of spines; whereas in the larva of bovis 
both this and the preceding segment are without spines. 
* See ‘‘ The Ox Bot in the United States; Habits and Natural History of Hypo- 
derma lineata,”’ by C. V. Riley (‘Insect Life,’ vol. iv. (Nos. 9 and 10) pp. 302-317. 
Bulletin of the United States Department of Agriculture, Washington, 1892), 
