90 Capt. L. Rogers— JlfaZrtn'a North of Calcutta. [July, 



12. Cryptocory7ie Grnddasiana, Prain ; Nat. Ord. Aroidew, from the 

 Kachin Hills. 



4. A list of the Asiatic species of Ormosia. — By D. Prain. 



(Abstract.) 



This paper gives a list of the Asiatic species (20 in number) of the 

 Legamiuous genus Ormosia with complete bibliographical references to 

 each of the previously known species. It provides a key to these species, 

 proposes tentatively a system of classification for those that are known, 

 and provides diagnoses and full descriptions of four forms, viz. : — 0. laoca, 

 Prain, a new species from the Kachin Hills ; inopinata, Prain, and 

 inopinata YAR. dubia, Prain, another new species which occurs in two 

 very distinct forms, also from the Kachin Hills ; and 0. Henryi, Prain, 

 an undescribed form from Central China. 



5. The food-plants of the Butterflies of Kanara District of the Bombay 

 Presidency, with a revision of the species of Butterflies there occurring. — 

 By Lionel de ]Sric:6viLLE, F.E.S., C.M.Z.S. 



6. Materials for a Carcinological Fauna of India, No. 6. — By Major 

 A. Alcock, I.M.S. 



7. The relationship of drinking loater ; water-logging and the dis- 

 tribution of Anopheles Mosquitos, respectively to the prevalence of Malaria 

 North of Calcutta. — By Leonard Rogers, M.D., M.R.C.P., I.M.S., 

 Professor of Pathology, Medical College, Calcutta. 



(Abstract.) 



In February last (1900), I carried out an inquiry into the health 

 of the tract of country just North of Calcutta and extending up along 

 the east bank of the Hooghly as far as Naihati, some 25 miles, with 

 special reference to the prevalence of malaria. The percentage of 

 people with enlarged spleens was taken as the most reliable test, and 

 over 5,000 persons were examined by myself, the degree of enlargement 

 of the organ being noted. The ground water levels were taken in as 

 many wells as possible, as the unhealthiness of this part has for years 

 been considered to be due to water-logging. The diinking water supply 

 was also noted, and the monthly number of admissions for fever in 10 

 of the principle dispensaries for the last six years was compared with 

 the monthly rainfall the order to ascertain the seasonal influences. 

 Lastly, some observations were made on the distribution of the 

 anopheles mosquito larvce. 



