170 VENOMOUS SNAKES AND THE PHENOMENA OF THEIR VENOMS 



found to be extremely variable, according to the kind of complement em- 

 ployed. Thus dog's complements produced very rapid solution of the venom- 

 ized corpuscles, while with those of guinea-pig and rabbit lysis proceeded 

 slowly, taking many hours to complete the reaction. In a second series of 

 experiments Flexner and Noguchi showed that the blood corpuscles of sus- 

 ceptible blood take up the haemolytic principle of venom by absorption. 

 The supernatant fluid obtained by separating the corpuscles from the venom 

 solution by centrifugalization becomes far less active upon the same kind of 

 cells, but is powerfully active upon the other kinds, to which it gives in turn, 

 by absorption, the haemolytic bodies electively if each is treated in succession. 



From these observations Flexner and Noguchi drew an analogy between 

 the mechanisms of venom haemolysis and serum haemolysis: whereas the inter- 

 mediary bodies in the first are present in venom itself, in the second both the 

 intermediary bodies and the suitable complements are present in the same 

 serum. In Ehrlich's terminology venom contains amboceptors and the serum 

 contains complements. (Plate 28.) 



Flexner and Noguchi next mentioned that venom, especially that of Crotalus 

 adamanteus, Ancistrodon piscivorus, and Ancistrodon contortrix, produces 

 agglutination of the washed corpuscles. With the defibrinated blood or the 

 washed corpuscles mixed with suitable activating serum, there is only a 

 momentary agglutination or none, as the cells become quickly dissolved. 

 The more resistant the corpuscles and the stronger the venom solution, the 

 more pronounced and lasting is the phenomenon of agglutination. Venom 

 agglutinins are distinct from venom haemolysins. The corpuscles agglu- 

 tinated by ricin are readily dissolved by venom haemolysins, unless there is 

 a very prolonged action of the former, with more or less delay in liberating 

 haemoglobin from the firmly conglomerated stroma. 



The same authors studied the effects of venom upon leucocytes in vitro. 

 In studying the changes taking place in the leucocytes under the influence of 

 venom a warm stage (37 C.) was used, the edges of the cover-glasses having 

 first been sealed with vaseline. The leucocytes were obtained from the 

 pleural or peritoneal cavity by injection of chemotoxic substances. The 

 venom solutions varied from 10 per cent to 0.002 per cent in isotonic saline 

 solution. With cobra venom almost no effect was observed in a solution of 

 0.002 per cent, whereas 0.002 per cent of rattlesnake venom and 0.005 P er 

 cent of moccasin venom caused definite changes. 



Only the granular cells showed motility. Weak active solutions are with- 

 out immediate effect on motion, but begin to manifest an inhibiting action 

 after about an hour, the controls being still motile at the end of 2 hours or 

 longer. After the motility ceases, the cells in general, except the lymphocytes, 

 show increased granulation due to the appearance of coarser and more numer- 

 ous granules in the protoplasma, the nuclei coincidently becoming more 

 distinct. After 6 hours the majority of the largest granular cells have already 

 disintegrated, the nuclei having been liberated. After 24 hours most of the 



