EFFECTS OF THE VENOM 



269 



hurried respirations, and later stuporous. The skin is clammy and 

 covered with a cold sweat, while the swelling and discoloration 

 spreads considerably, reaching the trunk. In due course convul- 

 sions set in, and death ensues from failure of the circulation. The 

 post-mortem reveals congestion of the meninges and lungs with 

 fluid blood, and nothing else of importance. 



Bitis arietans. — -The puff-adder poison was found by Rogers to 

 work in much the same manner as that of Vipera russellii, but not 

 to be so poisonous. 



Echis carinata. — This is a very poisonous snake, and the effects 

 of its bite resemble that of the cobra. 



Wall records a case in which there was much local swelling, 

 passage of blood in the urine, fseces, and vomit, elevation of tem- 

 perature, and death from exhaustion, due to loss of blood, on the 

 ninth day. Martin and Lamb record another case in which there 

 was much swelling of the bitten part, due to exudation of liquid 

 blood. Pain and tenderness were felt along the nerves, together 

 with anaesthesia, extreme restlessness, with cold and clammy ex- 

 tremities, but no haemorrhages. Loss of consciousness, with de- 

 lirium, set in only a short time before death, which took place at 

 the twenty-fifth hour. 



Fayrer gives a good account of a chronic case, in which there was 

 depression and faintness, coldness of the extremities, with swelling 

 of the affected part, and marked haemorrhages from eyes, gums, 

 throat, nose, vagina, and under the nails. 



The CrotalidcB are typically represented by Crotalus horridtis of 

 America, which has been carefully studied by Weir Mitchell and 

 Reichert, and by Lachesis, which latter has been studied by Rogers 

 in India. 



Crotalus horridus .—The local effects are : — -oedema, swelling, dark- 

 ening of the parts with infiltration of incoagulable blood, breaking 

 down of the tissues, putrefaction, and sloughing. There is no clot- 

 ting of the blood, which, on the other hand, is fluid and incoagulable. 

 There is a marked fall of blood-pressure, and respiration gradually 

 ceases, due to the failure of the circulation, but there is no direct 

 effect on the respiratory centre, and the phrenics are not paralyzed. 

 The heart goes on beating after respiration ceases, but is slightly 

 weakened. Post-mortem examination shows haemorrhages into the 

 peri- and endo-cardium, and into the peritoneum and pleura, but 

 not in the brain or the medulla, while the whole portal system is 

 much congested. 



Rogers placed a loop of small intestine in an oncometer, and found 

 that fall of blood-pressure was associated with a vaso-dilatation of 

 the portal system, in which the blood was not clotted. This vaso- 

 dilatation he considers may possibly be due to the action of the 

 venom on the vasomotor centre in the medulla, and thinks that 

 he is supported in his theory by the appearance of Traube-Hering 

 curves in his blood-pressure tracings. Pearce notes acute glomeru- 

 lar lesions due to the endothelialytic body. 



