THE MOSQUITO PROBLEMS OP QUEENSLAND. O 
Mansonia umformis is known to be an efficient carrier of Filaria spp. 
and consequently is of some medical importance. 
Control of Freshwater Species. 
With regard to the control of these freshwater species, the problem 
is divided into two distinct parts — ( a ) In the neighbourhood of Cairns 
and further north, where Anopheles punctulatus is endemic, every 
endeavour will have to be made to keep this species in check to eliminate 
the possibility of epidemics of malaria. It is to be hoped that arrange- 
ments will be made to retain permanently one or two of the Army 
Malaria Control Units. If such a course is adopted, malaria will be kept 
in check in the only bad area in Queensland, a very satisfactory training 
organisation will be maintained for anti-malarial work, and trained 
personnel will be available immediately in the event of another war. 
(&) South of Cairns, control of freshwater mosquitoes is not justified. 
To attempt such a task would require the expenditure of millions of 
pounds, and their importance does not warrant such an outlay. None 
of the freshwater species are important vectors of disease and the 
nuisance they create, except on the fringe of larger towns or in country 
villages, is not sufficiently great to need elaborate control measures. 
(c) The Saltwater Problem. 
This problem is easily the biggest of the three and its solution 
most difficult and costly. Several species are considered to be saltwater 
species, but the following are the most important: — 
(1) Aedes vigilax. This exceedingly common species is found 
throughout the coastal areas of Queensland. It breeds in countless 
millions in the salt and brackish water swamps which are only too 
common on our coast. The shallow swampy areas behind the mangroves, 
particularly where, for some reason or other, fish are prevented from 
gaining access to the swamp, are the usual breeding-place of this 
mosquito. The adults appear to fly or be carried by winds into the 
coastal towns, and occur in such large numbers as to make life unbear- 
able. To give some idea of the abundance of this species, it can now be 
stated that it was frequently used in experiments to test mosquito 
repellents. In such experiments biting frequencies of over 200 a minute 
were quite common. Although it frequently bites indoors, the usual 
habitat is out of doors, particularly in gardens and similar situations, 
where it bites viciously day and night. Aedes vigilax is not considered 
to be very important as a carrier of disease, but it is a very great 
nuisance, and eventually the permanent control of this species will have> 
to be attempted. 
(2) Culex sitiens. This mosquito is usually found associated with 
Aedes vigilax, but does not occur in such large numbers. The habits of 
both larvae and adult are similar to those of Aedes vigilax, and. again it 
is important because of its nuisance effect and not because of its relation 
to disease. 
(3) Mucidus alternans. AVell known to all Queenslanders as the 
“Scotch Grey”, this mosquito is usually associated with Aedes vigilax 
and Culex sitiens. The larvae of Mucidus alternans are predaceous and 
usually feed on the larvae of Aedes vigilax and similar species. The 
mosquito itself is a large brown and white mosquito, the extraordinary 
size invariably creating a great impression on the person being bitten. 
Actually the pain of-rthe bite is not as sharp as that of Aedes vigilax, 
a much smaller mosquito. 
(4) Anopheles amid us. This species appears to take the place 
of Anopheles annulipes, which is not often found in brackish water. 
B 
