A monograph of the Anopheles mosquitoes of India / by S.P. James and W. Glen Liston.

  • Sydney Price James
Date:
1904
Catalogue details

Licence: In copyright

Credit: A monograph of the Anopheles mosquitoes of India / by S.P. James and W. Glen Liston. Source: Wellcome Collection.

    74/238 (page 52)
    The test-pool experiment. and Eurasian houses. It is probable that since the introduction of a pipe water-supply into Madras city, the numbers of this species have largely increased, for its larvae are only found in those wells which, since the introduction of the pipe water-supply, have been unused. A. maculatus.—The larvae of this species may be found further from houses than those of A. rossi, and whereas larvae of the latter species are usually found in muddy water, the larvae of A. maculatus pi'efer clear sandy or rocky pools. In the Duars its larvae were found in clear pools on a rice-field. In Hong-Kong (China) its larvae were found by one of us in the small marshy pools on the o-ranite soil of Kowloon. o Sufficient observations have not been made with regard to the remaining species of anopheles ” to enable their favourite breeding places to be particularised, but detaiils of the breeding places in which their larvae have been found will be given in Part II. Under unfavourable conditions the selection of suitable breedino- places by the different species is not of course so apparent, and many instances might be given tending to show that if all the suit- able breeding places near a village are dried up, anopheles ” will lay their eggs on any collection of waiter of any kind. The test-pool ” experiment of Stephens and Christophers in Africa is sufficient to prove this, and the same expedient for finding out whether adult ‘‘ anopheles ” are really present in a place or not, when all the natural breeding places have disappeared, has been frequently resorted to by observers in India. Even without making artificial pools in a village many examples of the fact that in the absence of more suitable breeding places, anopheles ” will lay their eggs in almost any collection of water, may, be found in nature. In one part of Calcutta (Hastings) in Junes when no breeding place could be found anywhere near, and no adults could be caught in the houses, larvae were found in the cisterns of water on the roofs of the houses. During the hot weather in Mian Mir (Punjab) also, when the irrigation canals had been stopped for some time, and there were no natural breeding place of any kind, “ anopheles ” larvae were found in very curious situations, as for instance in the swimming bath, in the horse troughs, in tins of water accidentally left about, in the small drains 52]