MOSQUITO LARVA) AND FRESHWATER FISH. 27 
As the object of the enquiry is to ascertain whether the fish 
might be of the same use as the fish ' Millions” (Girardinus peci- 
loides) of Barbados in keeping down mosquito larve and conse- 
quently malaria, it would have served no purpose if I had restricted 
my enquiry to that one species of fish, and I have therefore attemp- 
ted to collect species of all freshwater fish in the neighbourhood of 
the town of Singapore, and have made experiments as to whether 
they feed on mosquito larvz or not. 
Obviously only the smallest species of freshwater fish were 
found in the small ditches, and of these Haplochilus panchax, the 
~ Ikan mata lalat’’ of the Malays, seemed to be the most common. 
Like the “ Millions’ of Barbados, it belongs to the family Cypri- 
nodontidz, which, according to Giinther, includes the smallest fish 
known. It grows to only about 2’ in length, but notwithstanding 
its small size it is probably the best known of the local freshwater 
fish, not so much on account of its numbers, as from the very con- 
spicuous bright silvery spot on the top of its head. It is of slow 
moving habits, and generally keeps close to the surface of the 
water. We found it in the following places:—junction of River 
Valley Road and Leonie Hill Road; Tanglin Road; Botanic Gar- 
dens; off Orange Grove Road; Kim Kiat Road; Syed Ali Road; 
Gaylang Road; Teluk Blangah Road, but it could be found in 
almost any ditch capable of holding fish. It eats mosquito larve, 
but not greedily. 
Another small species, also common, though less so than the 
previous one, is the Hemirhamphus fluviatilis, Bleeker (Ikan jolong 
jolong). It is an ally of the Gar-Pike and the Flying fish, and it is 
easily recognised by its lower jaw being drawn out into a long beak. 
It grows to about 23” in length, and was found in the following 
places:—junction of River Valley Road and Leonie Hill Road; 
Orange Grove Road; Tanglin Road; Jervois Road; Kim Kiat Road; 
Teluk Blangah Road. It is a delicate fish, not always surviving the 
journey to the Museum. It is herbivorous, living on Algae and 
Waterweeds, and does not eat mosquito larve.™ 
A great favourite amongst sporting natives is the Fighting Fish 
(Betta pugnax, Cantor), or “Ikan pelaga’”’. It grows to about 34). 
It has a large ventral fin, drawn out to a point posteriorily, and its 
colour is a dull purple, which, however, changes into dazzling me- 
tallic colours when the fish is excited. It is very active, and ate 
mosquito larve greedily within a few seconds of their being given 
to it. We found it in Somerset Road; Jervois Road; Moulmein 
Road ; and in large numbers, especially, in the pond at the junction 
of Syed Ali Road and Thompson Road, which is being filled up at 
present. 
A larger fish than any of these above is the © Ikan sepat”’ 
(Osphromenus trichopterus, Pall.), belonging to the same family as 
*I have since repeated the experiment with the same result, and this fish 
seems to be the only one of those I examined which does not eat mosquito 
larve. 
R. A. Soc., No. 62, I9!12. 
