MOSQUITO LARVA AND FRESHWATER FISH. 29 
Somerset Road, but discovered them (those of Culex) only ina 
single pool, and that contained no fish. I then examined the com- 
pound of a Kuropean house in Killiney Road, which is unoccupied 
at present, and found the place littered with old tins full of the 
larvee of the Tiger Mosquito (Stegomyia fasciata). 
An examination of certain pools off Gaylang Road showed strik- 
ing results, from which, however, it might be rash to generalize. 
The pools were at the edge of the mangrove zone, they were numer- 
ous, and had been formed to a great extent as depressions between 
the mounds of the Cray-fish Thalassina anomala, which is so com- 
mon in such localities. One of the pools was thick and black with 
mosquito larvze (Culex), but contained no fish ; another pool, only 
SN a yard off, was free from larve, but contained fish (Ikan mata 
lalat). 
We also examined the most malarial region in Singapore, the 
swamps of Teluk Blangah, and found mosquito larve in the follow- 
ing situations: in empty tins lying about; in freshly formed pools 
at the top of the reclamation ; in a small pool, at a level with the 
main pool, which contained only a single specimen of a fish (Ikan 
mata lalat); and, finally, we found numbers of the larve of Anc- 
pheles in the dense masses of waterweed in the largest pool there, 
the weed being so thick that probably no fish could penetrate it. 
Besides, the weed was so full of other minute animal life, that, even 
if a fish had penetrated there, he could scarcely have been expected 
to devote himself entirely to the mosquito larvae. The open and 
clean stretches of water in the pool contained several species of 
fish (Ikan mata lalat, Ikan jolong-jolong, Ikan betok, Ikan sepat, 
Ikan aruan and Ikan keli), but wedid not notice any mosquito 
larvee there. 
The pond at the junction of Syed Ali Road and Thomson Road, 
which is being filled up at present, certainly contained mosquito 
larvee (Culex) in places which seemed quite accessible to the numer- 
ous fish in it, but the general microscopic life there was so abundant 
that there was no need for any fish to restrict its diet to mosquito 
larvee especially. 
Whether the fish “ Millions’”’, if imported into such a locality, 
would show a marked predilection for mosquito larve, is doubtful. 
It is also uncertain whether it would be able to hold its own against 
theseveral species of fish indigenous to Singapore Island. In Barba- 
dos it is only the freshwater fish known (see Captain Vipan’s letter 
in Proc. Zoological Society, February 1910, pp. 146-147), and it 
may not be equal to the competition with any other fish. How- 
ever, as the Agricultural Department of Barbados has arranged to 
send from time to time consignments of © Millions” to the Zoologi- 
cal Gardens, London, from there to be distributed through the 
Colonial Office to various tropical Colonies, the experiment of bring- 
ing some to Singapore should be easy and inexpensive, best perhaps 
on a troopship in charge of the ship’s surgeon. But it must be 
remembered that to introduce an animal into another part of the 
R, 4. Soc., No. 62, 1912. 
