Anopheles rossi. 



edge of this surface (p. 39, fig. 8, 3). Both the external and median 

 frontal hairs of the larva are simple and unbranched. Palmate hairs 

 are present from the second to the seventh abdominal segments ; 

 the terminal filament of each leaflet of the palmate hairs is very 

 long. The pattern on the dorsal surface of the head of the larva 

 is characteristic and fairly constant. 



Habitat and observations. A. rossi is common throughout 

 India, and has been found at elevations above 5,000 feet. Its 

 favourite breeding place is usually a muddy pool or shallow tank 

 among native huts, and after the rains both larvae and adults may 

 be present in enormous numbers. In the Punjab (Lahore, Mian 

 Mir), it is rare before the commencement of the rains, owing pro- 

 bably to the absence of suitable breeding places, for it does not 

 usually breed in the irrigation watercourses as A. culicifacies does. 

 In September, October and November, however, enormous numbers 

 can be caught in the native huts. The larvae of this species have 

 occasionally been found in very foul water, and at Ennur near 

 Madras, its larvae were found in water containing 2*8 per cent, of salt. 



In the Deccan, in Bombay, and in Calcutta the larvae are found 

 in tanks during the dry weather. During the rains they disappear 

 from the tanks and are found in large numbers in the small shallow 

 muddy pools which are then so common by the roadside and in the 

 open fields. 



In the south of India, where suitable breeding places are 

 present all the year round, A. rossi has no special seasonal preva- 

 lence and is common throughout the year. In the Madras Presi- 

 dency it breeds largely in irrigated rice-fields. 



A.dult insects of this species are very commonly found in India 

 in railway carriages, as well as in almost every kind of road con- 

 veyance, and this is possibly one of the ways by which the species 

 has become so widely distributed throughout the country. 



Outside India it occurs in Penang, the Malay States and 

 Sumatra. 



It has been shown that under experimental conditions the 

 parasites of human malaria are capable of developing in this species, 

 but, although so prevalent throughout India, it has never yet been 

 found infected in nature. In the south of India it is one of the 

 carriers of Filariasis, 



[in 



