City And Suburban Areas.
The mosquitoes concerned are Culex pervigilans, C. fatigans and Aedes notoscriptus.
C. pervigilans may be described as the house and garden mosquito, and can be found breeding in every conceivable type of pond, drain, puddle or receptacle containing clean or polluted water.
C. fatigans is the street and gutter mosquito, breeding chiefly in barrels or pits containing liquid manure, in pools filled with seepage from manure heaps or decomposing refuse and in streams such as Motion's, Cox's and the Newmarket-Parnell creeks, which sometimes carry sewerage overflow.
Aedes notoscriptus, the mosquito of gardens and. gullies, is more selective in its choice of breeding place. It never lays its eggs where direct sunlight strikes, but makes use of a great variety of water containers and occasionally of street gully-traps, provided they are screened by grass, scrub or trees, and of drains on the sunless side of buildings.
This generalization is by no means exact: there is overlapping of breeding places, and all three mosquitoes might be found together in such a suitable spot as in foul water under the shade of trees. (Pl. 19, fig. 1.)
A very considerable, if not the greater proportion of mosquitoes which disturb residents, is bred in their immediate neighbourhood, in fact, on their own premises. It was a daily experience, while studying the city conditions, to demonstrate this to surprised people in every part of the city and suburbs.
The remedy is in their own hands. Permanent garden ponds should be stocked with goldfish or Gambusia: water tanks or barrels should be covered, guttering or spouting should be kept clean and in repair, wash tubs and similar containers should be emptied every week or ten days and gully-traps should be treated with an ounce of powdered bluestone (copper sulphate) or with kerosene, waste oil or disinfectant. Liquid manure should be screened or made up in small quantities for immediate use.
A few drops of oil should be placed in the bases of banana palms and, most important of all, long grass or weeds should be scythed or rooted out and the tins and rubbish which will almost invariably be revealed, cleared up.