196 



NOTES ON TWO SPECIMENS OF SPITTING-SNAKES FROM SOUTHEBN EHODESIA 



neck to the ground, in which position attempts at spitting woukl not be hkely. When 

 in the Karoo, Dr. Lefeuvre liiniself had never had to treat a case on whom a snake 

 had spat, but had heard from Dutch farmers that they had had to do so. Where 

 snakes are less common, as in Southern Rhodesia, people are apt to be less cautious. 



Identification 



The famous authority on Snakes, Mr. G. A. Boulenger, of the Natural History 

 Department of the British Museum, lias been kind enough to examine and report on 

 these specimens, both of which prove to be Naia niyricolUs. The larger is shown in the 

 drawing, of natural size, by Lady Dorothy Stanley. The illustration serves to bring out 

 some of the points in identification mentioned in Mr. Boulenger's letter to the Field 

 of February 1, 190H, quoted in e.rfenso hereafter. The larger snake, of a dark leaden 

 colour, measured 6 feet 9^ inches, the smaller 3 feet 4J inches. Both terjuinated in 

 narrow whip-like tails. It is interesting to note here that in the Third Eeport of the 

 Wellcome Tropical Bet:ea.rcli Laboraforiex, Khartoum, Dr. Franz \Verner, in a paper 

 on the Poisonous Snakes of the Anglo-Egyptian Sudan, refers to the black-necked 

 cobra, Naia niyricolUs, which had been brought in from Gondokoro, and which in 

 his presence "spat or rather ejected its venom" at his friend Dr. Sassi "after some 

 chewing movements of the jaws." 



Venom 



Venom, not 

 saliva, ejected 

 by 



" Spitting- 

 snakes" 



The snakes, through my ignorance, were unfortunately preserved in a mixture of 

 formalin and spirit, and were therefore rendered useless as regards experiments with the 

 venom. Dr. C. J. Martin, F.E.S., Director of the Lister Institute, London, who has done 

 much experimental work in connection with the snakes of India, etc., informs me that 

 formalin combines with the venom to form a compound rendering it useless for 

 experimentation. This should be remembered by travellers sending home specimens for 

 investigation. 



The term " SpMing-Snake" is clearly a misnomer, as also the use of the word 

 "Saliva" for the fluid ejected. The perusal of many accounts makes it clear that this 

 fluid is the venom, not the saliva. Indeed, but little saliva is secreted except during 

 actual mastication, and a consideration of the anatomy of the labial glands providing 

 the saliva in snakes makes it certain that no mechanism exists for its expulsion to a 

 distance in the way generally described. The snake, to eject its venom, requires to be 

 in the erect position, with its head drawn back, and so poised as to allow the fluid to 

 be ejected forward and upwards — a condition impossible when its capture is effected, as 

 it is done by Boer farmers by means of a forked stick pressing the snake's neck firmly 

 into the ground. 



During the first half of 190S, numerous contributions to the subject of Spitting- 

 Snakes appeared in the Fielil newspaper, letters or notes being published on 

 January 11, 18, February 1, 15, March 21, 2H, and April ly. The most important 

 letter, dealing with many of the points previously raised, was Ijy Mr. Boulenger, and 

 it is so valuable that I reproduce it here. 



