488 SNAKES OF CEYLON. 



(c) " Leucolysin " by destroying white blood cells, 



reduces the normal power of the system to resist 

 microbic invasion of all sorts. 



(d) This aids the action of (4) (c), if indeed it is a 



separate entity. 



(5) (a) " Hasmorrhagin," by damaging the lining 

 membrane of the arterioles, allows leakage of the 

 vessel contents. It in conjunction with (4) (a) 

 favours the occurrence of haemorrhages. 



(6) The local destruction of cells accounts for sloughing 

 of the wounds, and leaves an ulcer when the dead 

 tissues have separated. 



(l) Symptoms in Man — Local : The first, and perhaps 

 invariable symptom, is pain, which is of a stinging or burning 

 character out of all proportion to the mechanical injuries 

 sustained. It comes on immediately and persists, perhaps 

 lasting for hours. If pain is experienced only to the degree 

 excited by ordinary pricks or scratches and is but transient, 

 there is a justifiable presumption that poison has not been 

 introduced. Coincident with the pain, and almost as speedy 

 in its appearance, is swelling, which gradually increases until 

 perhaps the whole limb is puffy. The third sign that venom 

 has gained access to the wounds is the oozing of a blood-stained 

 serum. If, on the other hand, the punctures are sealed with 

 clot, as in ordinary wounds shortly after injury, there is every 

 probability, if not actual certainty, that poison has failed to 

 find entry into the tissues. The fourth cardinal sign is one 

 which cannot be detected until the tissues in the site of the 

 wound have been cut into, though it may be inferred if rapidlj' 

 ensuing swelling has occurred, accompanied with the other 

 signs the tissues assume a very characteristic appearance ; 

 the parts become purpUsh centrally, the colour fading to 

 scarlet and then pinkish, and a thin serum exudes. In one 

 case, Wall (A. J.) found this purplish effusion, which is 

 characteristic of the action of snake venom, within 30 seconds 

 of the injection of the poison. When present, it is absolute 



