"TE. AUSTRALIAN NATURALIST. 8 
Mr. Thackeray described fully, and some very clear pictures 
of coastal and table-land river resorts. 
After the lecture quite an interesting little discussion on the 
subject of art arose, and so divergent were the views expressed 
that the thought was suggested that someone could be induced 
to deliver an instructive lecture, capable of elaborate illus- 
tration by coloured plates and paintings, on the subject 
“The Artist and the Naturalist.”’ 
A vote of thanks was accorded the lecturer for his ad- 
dress.” i 
THE HOUSE-FLY. 
(By Rex. W. Bretnall.) 
Tue house-fly (Afusca domestica) is familiar to everyone, and 
is distributed over the greater part of the globe. 
The imago is of a uniform black colour, but has a somewhat 
brown appearance owing to a coating of grey tomentum. The 
eyes are red, and the thorax and abdomen coated with stiff 
black bristles; the distinguishing feature, however, is the 
presence of four parallel black lines on the thorax. The eggs 
are laid in stable manure or house refuse, and hatch out with- 
in eight hours. Professor Howard, of the United States De- 
partment of Agriculture, gives the periods of development as 
follows :—From deposition to time of hatching, the oggs take 
one third of a day; hatching of larva to first moult, one day ; 
first to second moult, one day; second moult to pupation, 
three days; pupation to issuing of adult, five days. ‘Total, 
ten days. <A single individual lays about 120 eggs. The 
house-fly is a recognised agent in the spreading of diseases such 
as typhoid, tuberculosis, etc., and for its obliteration united 
action would be necessary. All garbage bins, etc., should be 
kept covered. Wire gauze over doors and windows forms an 
efiective method of keeping flies out of the house. In cases 
where decaying matter, such as gardening manure, cannot be 
covered, it should be treated with kerosene or chloride of lime. 
Several remedies or ‘‘checks’’ are in use, one of which is 
being found very effective in America is as follows:——A little 
of a saturated solution of camphor in pure carbolic acid is 
placed in a shallow dish over a spirit lamp. The vapour evol- 
ved is quickly fatal to flies. Mr. Froggatt recommends the 
following formalin treatment:—About a quarter of an inch 
of sand is placed in a soup plate, over which a couple of sheets 
of blotting paper, cut to size, are placed. Sugar is then 
sprinkled over the surface, and the whole saturated with di- 
lute formalin (1 of ordinary formaline to 20 of water) and the 
dish placed in a well-lighted place. Flies will then be attracted 
