112 



Forty-third Report on tee State Museum. 



[16] 



The ox warble-fly, H. bovis, is found in both North America and 

 Europe, and is a quite common species. When a large number of the 

 warbles occur in a single ani- 

 mal, its health and condition 

 are seriously impaired, and 

 the value of its hide for con- 

 version into leather greatly 



depreciated. ^^«; ';-^\« °^ 



^ war Die -fly, natural 



As very few persons are size. 



familiar with the appearance of the fly, or 



would be able to recognize it, although it might 



Fig. 2.-The ox warble- be hovering with evil intent about their cattle, 

 fly. Hypodkema bovis, en- „ „ . , , . , , , ^ 



larked. figures 01 it are herewith presented, accom- 



panied with such description as will enable any one to identify it 

 beyond all doubt whenever it may be encountered. Figure 2 (after 

 Verrill) represents the fly, enlarged, and Figure 3 (after Ormerod) in 

 its natural size. 



Description of the Fly. 

 It will be seen that it measures a little more than half an inch in 

 length. It is heavily covered with hair, except the thorax, which is 

 partially naked, black, and twice broadly banded with white and yel- 

 low. The abdomen is also black with a white or yellowish band at 

 its base, a black band over its middle, and a reddish-orange band of 

 hairs at its tip. The head is large, and its front is ash-colored with 

 yellowish-white hairs. The wings have a brown tinge, and are 

 unspotted. The legs are black, with lighter feet. Some writers have 

 compared the fly, in appearance, with a humble bee, its general shape 

 and the yellowish hairs of its body being the points of resemblance. 



Life-history. , 



It has not yet been ascertained how the egg is deposited by the fly, 

 whether simply attached to the skin, or if inserted into it by means 

 of its long, extensile ovipositor, which has been described as gimlet- 

 like. Nearly all the subsequent life-history of the insect has been 

 fully worked out, and for mUch of our later knowledge of it we 

 are indebted to the earnest and successful labors during the past two 

 years of Miss Eleanor A. Ormerod, Consulting Entomologist of the 

 Royal Agricultural Society of England. The following items in its 

 life-history have been mainly drawn from an illustrated paper on 

 " "Warbles," by Miss Ormerod, published in the Mark Lane Express, of 

 April 25, 1887: 



