Description. 



When the perfect insect leaves the chrysalis, it 

 forces open a very remarkable marginated trian- 

 gular lid, which is situated on one side of the 

 small end. This insect is the largest of the Eu- 

 ropean species, and is very beautiful : it is, how- 

 eve^ the terror of cattle, as it inflicts great pain 

 when depositing its eggs. 



The horse gad-fly is distinguished from the 

 rest of its tribe by having a black band in the 

 middle and two dots at the tip of its whitish 

 wings. The abdomen is yellow brown, with 

 black spots at the divisions of the segments. 

 The female is more brown than the male, and 

 has her abdomen elongated with a cleft terminal 

 style. The larvae are tbose odd-looking grubs 

 which are commonly found in the stomach of 

 horses, and sometimes, though much less fre- 

 quently, in the intestines. Here they hang in 

 clusters of from half a dozen to more than a 

 hundred, adhering to the inner membrane of the 

 stomach, by means of two small hooks or tenta- 

 cula at their heads, whose points turn outward. 

 When they are removed from the stomach, they 

 will attach themselves to any loose membrane, 

 even to the skin of the hand. To do this they 

 draw back their hooks, which have a joint near 

 their base, almost entirely within their skin, till 

 the two points come close to each other ; then, 

 keeping them parallel, they pierce through the 

 membrane, and immediately afterwards expand 

 in a lateral direction, and by these means they 

 become perfectly fixed. 



VOL. vi. NO. 46. 2 s 



