A NOTK ON 111 10 SUUAX Si'ittink-Snakk 



BY 



Sn; Thomas K. Fkaseii, M.D., F.R.S. 



So far as the very small quantity I received would allow, I have examined the specimen 

 of the venom of the "Spitting-Snake," which was kindly sent to me by Dr. Andrew Balfour 

 of the Wellcome Tropical Research Laboratories, Khartoum. 



This specimen possesses the interest of being the actual venom ejected a considerable 

 distance by the serpent. At the moment of ejection it had been received on a Hat glass 

 plate, held before the serpent, and then quickly dried on the plate which was sent to me. 

 The serpent itself was not identified.* 



I found that a dose of 0-0035 gramme per kilogramme, injected subcutaneously, was 

 sufficient to produce death in white rats. The small quantity at my disposal was 

 insufficient for the determination of the exact minimum lethal dose. The symptoms were 

 similar to those produced by the venoms of the African cobra and of Sepedou kaiinachates, 

 which I had lately examined, f and, as in the case of these venoms, no conspicuous 

 blood changes were observed. On the whole, the probability is that it is the venom 

 of the African cobra. 



It is so well known that the Sepedon can eject venom to the distance of several 

 feet, that in some parts of Africa it is popularly known as the " Spuw Slang" or Spitting- 

 Snake. This habit of ejecting venom as a means of offence or defence appears, however, 

 to be exercised also by the African cobra, whose venom, likewise, is chiefly neurotoxic. 

 Venom thus ejected is not likely to produce general poisoning, or indeed, to do much 

 harm unless it reaches the eyeball, where severe local effects may follow. 



F. wkuvmi JVaia nigricollis (Sudani 



Head, seen from side, from above and below. Adult length = lapprox.) 2-400 metres 



* It was almost certsiiuly Naia niyi-imUis, the spitting cobra of the Sobat. — A.B. 



t Philosophical T ran.vtclion.i nf the Royal Socielij, Sei'ies B, Vol. 200, pj). 241-269 (iu ooujimotion with 

 Dr. A. G. Guuu). 



