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THE ANOPHELES OF KARWAR ( NORTH KANARA > 



(With a Plate.) 

 By H. Cogill, M.R.C.S., L.R.C.P., 



Acting Civil Surgeon, Sholapue. 



Of the known species of Anopheles occurring in India the following 

 were found by the author :— 



1. A. fiuviatilis, James. 



2. A. culicifacies, Giles. 



3. A. Jeyporensis, James. 



4. A, James i, Theobald. 



5. A. nigerrimus, Giles. 



6. A. barbirostris, van der Wulp. 



7. A. Rossi, Giles. 



In addition to these, five species, new to India, have been discovered. 

 Two of these were first found by Mr. E. H. Aitken, and have been 

 named A. Aitkeni and A. Karwari by Theobald. Two others have been 

 identified by the same authority as A. leucophyrus, Donitz, var. 

 A. elegans, and A. punctulatus, Donitz. The identity of the fifth species 

 has only recently been definitely settled, as the imago very closely re- 

 sembles J. Aitkeni. The isolation of the larva? has finally established 

 them as separate species, and the last has been provisionally named 

 A. culiciformis. 



Of the known species 



was noted as very common at certain seasons. It was 



A. fiuviatilis found from April to February (the period over which 



James, these observations extended). It first became really 



plentiful during the early rains towards the latter end 



of May and in June ; during the heavy rains in July to September it 



was scarce ; from October to January it was extremely abundant again. 



It is of interest to note that the malarial incident, as observed in 



cases treated at the Civil Hospital, Karwar, showed a marked rise 



during May, June and July ; from then to the end of October a very low 



rate ; and during November, December and January the maximum 



rate was reached. 



The larva of this species was found in all forms of slowly moving 

 waters including rice fields. The distinctive features of the larva are 

 too well kuown to need description ; it may be noted, however, that the 

 frontal bristles are by no means constant in character, as one or 

 more fine filaments are not uncommonly found on the median bristle. 



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