BOT-FLIES. 217 
in front of the suture, and with black ones behind, which 
form a well-marked transverse band; the abdomen is cov- 
ered with whitish hair in front, with black ones in the mid- 
dle and with orange-colored ones behind. The fly is smaller 
than the one described before, measuring from 9 to11mm.in 
length. 
Judging from the description given of the habits of this 
fly it seems that they are almost identical with those of the 
larger bot-fly. It is stated that the female prefers to deposit 
her eggs on the lips of the horse, and on the long hairs cov- 
ering them. This, of course, greatly irritates the animals, 
which is shown by their rubbing their lips against the 
ground, the fore-limbs, or trees. The eggs are said to be 
darker than those of egw. The adult larvae are smaller and 
deeper red, and they have also the habit of remaining for 
some time in the folds of the rectal mucous membrane, where 
they assume a greenish color before leaving the infested ani- 
mal. The young larve of this species may sometimes fasten 
to the epiglottis and in the pharynx, and thus can become 
dangerous to the horse. 
THE NASAL BOT-FLY. 
( Gastrophilus nasalis Lann.). 
This species of bot-fly is illustrated in fig. 179. The up- 
per surface of the thorax is clothed with dark hairs inter- 
mixed with others of a golden color; the anterior portion is 
much lighter colored, and fairly sharply separated from the 
darker posterior portion. The shining scutellum is ofa dark- 
brown, bright-brown, or a chestnut color. The color of 
the dense hair covering the abdomen varies in the different 
specimens; in the example illustrated it is white on the 
second, black on the third, and orange on the last segments. 
The wings are hyaline, and small for the size of the fly, 
which measures from 12 to 18mm. 
The elliptical white eggs are truncated in front, and are 
most frequently deposited upon the wings of the nose and 
on the lips of horses, hence the scientific name nasalis. 
_ Meigen and B. Clark designated this fly by such names as 
sdlutaris and salutiferus, to express the unfounded belief 
