LIFE-HISTORY OF THE FOREST FLY. 105 
That the Forest Flies are blood-suckers is a fact which has long 
been proved; but still it appears to me open to doubt whether it does 
not also draw in the moisture of the skin through its sucking-tube. 
There is a strong popular idea that it does so, and the fact noticed by 
Mr. D. D. Gibb, that it is by no means always that blood is to be found | 
within (on opening the fly), appears at least to point in the above 
direction. In the course of my own observations I found that some of 
the flies which I kept in confinement swept to and fro with the flexible 
extremity of the trunk on the part of the cardboard which I had slightly 
wetted, as if they were trying to imbibe the moisture. This point 
would, I think, be worth enquiry for practical purposes. 
Reverting to Mr. Gibb’s letters regarding methods of prevention, 
he mentioned :— 
‘‘ Well-groomed horses afford least attractions for these flies. The 
common remedy adopted by those driving in the Forest with an un- 
seasoned horse is to damp a cloth with paraffin, and rub lightly over 
the animal, particularly the parts beneath and under the tail, which 
are most subject to attack. For some years I have used, with excellent 
results, a carbolic sanitary fluid prepared by Mr. Johns (chemist), 
High Street, Southampton, which is clean and far from offensive in 
use, and effectual in keeping off Forest Flies. When added to hot 
water it mixes very readily, giving the water a milky appearance. For 
dressing, or rubbing over with a wet cloth, two tablespoonfuls to a 
gallon of water would be sufficient. To wash animals over, if desired, 
one pint to twelve gallons of water would be the quantities. Doubtless 
McDougall’s or Jeyes’ preparations would serve the same purpose. 
Train-oil is a very old remedy with natives of the Forest, but it is 
offensive and dirty.” 
The following practical remarks as to accustoming horses to attack were 
given me by Mr. Moens, of Tweed, Lymington, Hants. On the Ist of 
June, Mr. Moens wrote :—‘ With horses strange to the Forest Fly we 
put some flies on them and, seeing that their head-gear is good, let 
them kick themselves until tired in the stalls. After a short time we 
find horses get used to them, but some never will. When the flies 
trouble them much, the thing is to keep the horses going fast, so as to 
get very hot, as the flies do not care for this *; the worst thing is to 
stop them, unless one stray fly is on the flank, when it is easily caught 
with a clap of the open hand.” 
Lire-nistory or THE Forest Fry, H. equina.—The important part 
in the life-history of this fly is that, like others of the division of the 
* Conjecturally, because the perspiration amongst the hair keeps them from 
moving about freely, and also clogs the fine apparatus of their feet. See Plates, 
