TOXIC SECRETIONS OF VENOMOUS SNAKES 



75 



MORTALITY CAUSED. 



The mortality from snake bites is naturally greater in those countries where 

 poisonous snakes are more abundant and the conditions of human Hfe favor 

 exposure. According to Fayrer, in 1869 there were 11,416 deaths from snake 

 bites in Bengal, Assam, Orissa, Punjab, Oude, and Burma, a district which 

 contains about 121,000,000 inhabitants, and perhaps almost 20,000 men, i. e., 

 16 out of every 100,000, are killed each year. In Bengal alone 7,595 men 

 in 1874, and 8,807 in 1875, were killed by snakes. 



In the years from 1880 to 1887 the yearly average loss of the lives of 19,880 

 human beings and 21,412 cattle was reported. In 1888, although 578,435 

 poisonous snakes were destroyed 22,480 human lives were lost, and in 1889 

 the snakes killed numbered 510,659 and the fatahties to the human race 

 21,412. These alarmingly high mortality statistics may be attributed partly 

 to the frequent invasions of poisonous snakes into human residence and 

 partly to the powerful venoms they are provided with. Cases are known 

 where venomous snakes have secreted themselves in the bed or in stockings 

 or shoes and fatally bitten the owners. In India the cobra Naja tripudians, 

 though smaller than the king cobra Naja bungarus, is the most dreaded. 

 Of Bungarus, the common krait, B. cceruleus, is more dangerous than the 

 other kraits. Dahoia russellii and Echis carinata are fatal in their bites. 



The bites of Ladiesis flavoviridis, better known as Trimeresurus riukiu- 

 anus, are fatal in the ratio of slightly over 15 per cent of the entire number of 

 persons bitten. The following figures show the analysis of the results of 

 the bites of Trimeresurus. 



Table 2. 



Thus each year the average number of persons bitten is 225.3, and 29.2 

 deaths occur out of this number, making about 15 per cent mortality. If we 

 take the total number of the inhabitants of the islands of Riu Kiu into 

 consideration these figures are by no means small. The total population of 

 the Okinawa prefecture is only 500,000. The accident statistics will be 

 about 5 per milU, and the mortality 52.6 per 100,000. 



Calmette estimates the mortality from cobra bites at 25 to 45 per cent. 

 Imlach gives 20 per cent mortality, based on 306 cases of Indian snake bites. 



