79 



^x definite subdi visional areas, based on the distribution of Anophelines 

 Ihese are the Indo-Gangetic. Trans-Indus, Malabar. Peninsular* 

 Assam-Burma, and Himalayan areas, for each of which the Anopheline 

 tauna is listed. Broadly speaking, two types of Anopheline fauna are 

 distinguishable in the Indian Empire, the first occurring in the Indo- 

 Gangetic tract, the Deccan and, to some extent, in the Peninsular 

 area generally ; the second in the countries east of Calcutta and the 

 Malabar tract, with Ceylon and possibly, to some extent, the coastal 

 and hill areas of the Madras tract. It is remarkable that it is chiefly 

 m the degree of absence of Malayan forms that these differ It seems 

 legitimate to say that the Indian area is characterised by an im- 

 poverished Malayan Anopheline fauna, the impoverishment reaching 

 a high degree in the first series of tracts and being but little marked 

 m the second Of 45 African species only four are common to Africa 

 and India while of 32 Malayan species 21 are common to Malaya and 

 India ; 32 additional species are Indian only. Certain Indian species 

 seem to have a zoocentre included in the Indian Empire, and these 

 help to make good the impoverishment of Malayan forms in a large 

 part of the area. These species often have a westerly tendency of 

 occurrence ; for example, ^. stephensi, unrecorded in Malaya, stretches 

 to the confines of the Arabian desert, and A. culicifacies, a dominant 

 Indian form not recorded from Malaya, occurs as far westward as 

 Arabia and Palestine. More strictly Indian still are A. theohaldi, 

 A . willmori and A . fowleri. 



With regard to the Himalayan species, A. gigas is Malayan, and 

 has been found m Java and probably in the Philippines. The common 

 and ubiquitous Himalayan form is A. lindesayi, which appears not 

 to be known out of India. Two other species occurring in the Hima- 

 layas, and not elsewhere m India, are the two tree-breeders, A hari- 

 anensis {lio\^.xcilc) and A. annandalei (Malayan). The Himalayan 

 fauna also occurs at high levels in the Assam and Peninsular areas 



The distribution of Indian Culicids other than Anophelines is also 

 briefly discussed. Of 142 African and European species, 12 only 

 occur m India, and of these some are very widely-distributed such as 

 Aedes argenteus {Stegomyia fasciata) and Culex fatigans But of 161 

 Malayan species, 56 occur in Malayo-India and at least 10 in Hindustan 

 Of 95 species recorded from Malayo-India, 40 only are at present not 

 recorded from Malaya. At least 22 of these species are found also in 

 Hindustan. Though not to be considered as strictly accurate these 

 figures indicate that the rich fauna of moist, tropical Malaya'is stiU 

 tound m forests and moist jungles wherever they occur in India 

 while m the relatively drier parts of India this heavy jungle fauna 

 domSic 1o?m^^''' ^^^""'^^ ""^'^^^ *^^ swamp-breeding, agrarian and 

 In the case of the mosquito fauna of India, one can trace the east- 

 ward recession, due to drier climatic conditions, of a faunal area which 

 once extended from Europe to the East. There is, however, much 

 in the distribution of mosquitos due to special circumstances affecting 

 individual species. The explanation of the area of distribution of 

 certain species is not clear, yet these must have a definite significance 

 It is not understood why some species stop at the Indus, nor why 

 tor example. Anopheles stephensi should occur up the Tigris and 

 Euphrates, while A. culicifacies does not. 



Further knowledge in regard to the Central Asian border is most 

 desirable, as also are observations and collections from the Thibetan 

 and Chinese borders. 



