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mosquitos have been found : — Anopheles (Myzomyia) culicifacies, 

 A. listoni, A. {Neocellia) stephensi, A. {Nyssorhynchus) fuliginosus, 

 A. jamesi, A. (Pyretophorus) jeyporensis, A. (Nyssomyzomyia) rossi, 

 A. punctulatus and A. {Myzorhynchus) barbirostris, these being the 

 same species as those found on Bombay Island by Dr. Bentley, with 

 the addition of A. jeyporensis and A. punctulatus. Of a total of 

 about 2,000 insects captured 87 per cent, were found to be 

 A. rossi; the next most prevalent species was A.fulginosus, 6' 9 per 

 cent, on the east side of the island and 8* 3 per cent, on the west 

 side, followed by A. barbirostris, 2" 8 per cent, and 2' 2 per cent, 

 respectively. The proportion of A. rossi larvae found varied greatly 

 with the weather. They almost disappeared after a few weeks of 

 dry weather, but re-appeared after a single shower of rain, and at 

 some places are to be found in every puddle or hoof-print. 



The occurrence of A. rossi in wells examined is not given, but of 

 other species A. barbirostris constituted 33' 7 per cent, of the larvae 

 found ; A. fuliginosus, 16-87 per cent. ; A. culicifacies, 34*37 per cent. ; 

 A. listoni, ir87 per cent.; A. jamesi, 3-12 per ceut. In borrow- 

 pits along the railway mosquitos continued to breed very late in the 

 season and long after most other temporary breeding places had 

 dried up. Although no rain had fallen since the beginning of Sep- 

 tember, larvae were found in 55 of these pits late in October ; about 

 87 per cent, of the larvae (excluding those of A. rossi) consisted of 

 A. fuliginosus, 8" 6 per cent, of A. barbirostris and 4*3 per cent, of 

 A. cvlicifacies. 



Details are given as to the general breeding places of each species 

 throughout the island, with notes as to their prevalence on the main- 

 land. In the absence of dissection of adult mosquitos to discover 

 which of them are the carriers of malaria in the island, no definite 

 indication can be found from the distribution of Anopheles in Salsette. 

 The species which have a reputation elsewhere as rural malaria-carriers 

 are to be found in places which, as tested by the spleen census, are 

 quite free from malaria, as well as in places notoriously subject to it. 

 Whatever the carrier may be, it is evident that something more than 

 the presence of facilities for breeding in abundance is required. There 

 must be sufficient damp and shelter from the wind to enable the female 

 to survive in considerable numbers till she becomes infected and for the 

 parasite to pass through the necessary cycle. In the rural districts, 

 anything like a general attack on the breeding places of the mosquito 

 is out of the question, as they are not artificial, but natural and very 

 widely distributed. Borrow-pits along the railway should be abolished 

 or a connecting channel run through them so as to drain them effectu- 

 ally, and any excavations of the kind should be made in such a way 

 that they will drain promptly and completely into the nearest water- 

 course. Though the breeding places can scarcely be attacked satis- 

 factorily, an attempt should be made to deal with the resting places 

 of the adults. Villages outside the tree and grass-covered area and 

 completely accessible to sea breezes, are extraordinarily free from 

 malaria, and therefore it would be well to do what is possible to expose 

 other villages, less favourably situated, to the sea breezes. The 

 people should be encouraged to cut the grass early and keep it cut in 

 the immediate neighbourhood of the houses, and also on the side of 

 any hill which may command a village. 



