SNAKE VENOMS 175 



In the case of a cobra bite, according to Martin, the areolar tissue about 

 the wound is infiltrated with pinkish fluid ; the blood is often fluid ; the 

 veins of the pia are congested, and the ventricles often contain turbid 

 fluid ; the kidneys may show much congestion. When death occurs in 

 a few minutes, enormous general intravascular clotting is found, which 

 seems to be the cause of death. After death from a viper bite the site 

 of the wound is the seat of intense edema and extravasation of blood ; if 

 in the muscles, these are much softened and disorganized. Hemorrhages 

 are found in all organs and in the intestinal tract. If death occurs 

 after several days it is generally because of sepsis, and shows the usual 

 changes of this condition ; in addition, as a rule, to marked gangrenous, 

 ulcerative, and sloughing processes at the site of the bite. 



H isto logically there are found, in addition to innumerable hemor- 

 rhages in nearly all the organs, many vessels plugged with thrombi 

 composed of more or less hemolyzed, agglutinated erythrocytes. The 

 changes produced in the nervous tissue by the Australian tiger snake 

 are described by Kilvington, 1 who found marked chromatolysis, the 

 Nissl bodies breaking into dust-like particles, and eventually all stain- 

 able substance disappearing from the cytoplasm ; the nucleus retains 

 its central position, but often loses its outline and may disappear. The 

 cells around the central canal of the cord are most affected. There are 

 no inflammatory changes in the nervous system, and if death occurs very 

 quickly there may be no microscopic alterations. Hunter 2 found simi- 

 lar changes in the Nissl bodies in both krait and cobra poisoning ; in the 

 medullated fibers he found the myelin sheath converted into ordinary 

 fat. Nowak 3 studied experimental animals, and found much fatty 

 change in the livers, even if death occurred one-half hour after poison- 

 ing ; also focal necrosis in the liver, acute parenchymatous alterations in 

 the kidney, and pneumonic patches in the lungs. 



Effects on the Blood. There has been much discussion concerning 

 the part played by the abundant and prominent intravascular clotting in 

 causing death after snake-bite. Lamb 4 states that when venoms are 

 slowly absorbed the coagulability of the blood is decreased and it is found 

 fluid after death, but when a fatal dose of venom (viper) is rapidly 

 absorbed, clotting is increased and thrombosis is the chief cause of death. 

 Martin has demonstrated very active fibrin ferments in snake venom 

 (loc. cit. ). It is highly probable, however, that many of the thrombi 

 of venom poisoning are not produced by coagulation of fibrin, but by 

 agglutination of the red corpuscles, which Flexner 6 has shown can 

 cause large clots in the heart and great vessels, as well as "hyalin" 

 thrombi in the small vessels. 



Nature of Venoms. The varied effects produced by 

 venoms have been found to be due to a number of poisonous 

 elements which they contain, and which have been distinguished 

 and separated from one another by Flexner and Noguchi. 6 



1 Jour, of Physiol., 1902 (28), 426. 



2 Glasgow Med. Jour., 1903 (59), 98. 



3 Ann. d. 1' Inst. Pasteur, 1898 (12), 369. 

 * Indian Medical Gazette, Dec., 1901. 



5 Univ. of Penn. Med. Bull., 1902 (15), 324. 



6 Jour. Exp. Med., 1903 (9), 257; Univ. of Penn. Med. Bull., 1902 (15), 

 345. 



