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(at the foot of the Himalayas) it is as high as seventy- 

 two (Fig. 67). We found, however, that there was one 

 important matter in which the Duars differed from 

 Calcutta, and that was in its Anopheline fauna. 

 Whereas in Calcutta M. rossi was the predominant 

 species, in the Duars M. listoni was the commonest 

 Anophfline. 



Again, in the Jeypore district (Madras), we had 

 a district of uniformly high endemic index (50-100), 

 and here we found an Ano-pheline, P. jeyporensis, which 

 we had not encountered elsewhere, so that the view 

 seemed tenable that the high endemicity of these 

 districts was dependent on their special Ano-pkeline 

 fauna. To test to what extent species was concerned 

 in determining endemicity, we then made use of 

 another more exact method, viz., determining by 

 dissection whether any difference occurred amongst 

 the different species in the percentage of infected 

 specimens : we were able to carry this out in the case 

 of M. rossi and M. culicifacies. We caught these 

 species in the same huts in the same villages at the 

 same time, and determined by actual dissection the 

 percentage of glands infected with sporozoits. The 

 results were most striking, and fully confirmed our 

 previous idea, based on more general considerations 

 of the importance of species. They were as follows : 



I. MIAN MIR (PUNJAB) 



