30 INSECTS AFFECTING DOMESTIC ANIMALS. 
In such cases a teacupful of kerosene poured into each vault at intervals of a 
month or less, would greatly decrease the annoyance from mosquitoes, if it did not 
altogether prevent it. This is a case where tho cooperation of neighbors is most 
essential; every householder in a given neighborhood should see that his vault is 
treated with kerosene regularly and often. The cost is so trifling that it need not 
be considered. 
When, as is the case at many country homes, rain water is collected in barrels or 
hogsheads, for one purpose or another, mosquitoes may and do breed in numbers in 
such vessels. If the water as used be drawn from the bottom of the cask, it will do 
no harm to pour in a little kerosene, since the oil will not be drawn out with the 
water. At all events, such receptacles should be covered at night to prevent egg 
laying. 
The question what is the best way to cover with kerosene the surface of a pool of 
some size is apparently needless, since the operation is obviously simple, but such a 
question has been asked of the Division. Simply pouring the oil on from any point 
of the shore will answer tolerably well, since it will spread of itself, but if for any 
reason it is desired to coat the pool rapidly with kerosene, it may be advisable to 
spray the oil through a spraying nozzle, either from the bank or froma boat. The 
method of application will vary with each case, but in the class of pools which can 
be most advantageously treated, namely, those of small size, the oil can be well 
spread by throwing it on to windward with a wide sweep of the arm. 
Family CHIRONOMID 4. 
(Midges.) 
The insects of this family are mosquito like, but differ, in that the 
costal vein is not continued around the wing. The antenne of the males 
are usually plumose. The Jarve breed in still water, and for a species 
which has been present in great numbers in the water mains of Boone, 
Iowa, and which occurs in water tanks and reservoirs, it has been 
determined that the larve form a protecting tube of earthy particles 
and bits of organic matter, the pupz coming to the surface to permit 
the emergence of the adult (Bull. 32, lowa Exp. Sta.). 
THE BLOOD-SUCKING GNAT. 
( Tersesthes torrens Towr ..) 
This species, described from western New Mexico, is the type of a 
new genus, Tersesthes (Psyche, Vol. VI, p. 369). These gnats, accord- 
ing to Townsend, occurred in some numbers upon horses, mostly on the 
head and face, particularly around and below the eyes of the animals. 
They were very small and black, but their abdomens being distended 
and swollen with blood gave them a red appearance. The locality 
where they were taken was at an altitude of “something over 7,000 
feet.” This species has not been recorded from any other locality and 
would seem to have a restricted range. 
It is described as being 12 mm. to 24} mm. long, according to the dis- 
tension of the abdomen, the wings 14 mm., the general color blackish, 
wings grayish, transparent, with barely a smoky tinge. For further 
details the original description should be consulted. 
