88 VENOMOUS SNAKES AND THE PHENOMENA OF THEIK VENOMS 



lecithin and sufficient cobra venom, shaken as usual. He obtained four 

 preparations: 



Substance I. A spontaneous precipitate formed in the watery layer when the 

 latter is separated from chloroform (lecithin solution) by means of i volume ether 

 and two-fifths volume of alcohol. It gives a biuret reaction and many other protein 

 reactions — precipitation by potassic ferrocyanide, acetic acid, nitric acid, tannic 

 acid, picric acid, and alcoholic cadmium chloride solution. Haemolytically very 

 weak (one-tenth of the original venom), but can be complemented with lecithin. 



Substance II. Obtained by first precipitating the watery portion with 5 per 

 cent phenol, then the oily matter which separates out thereby is again precipitated 

 with alcohol. The precipitate has the property of becoming 10 times more hsemo- 

 lytic than the native venom when combined with enough lecithin, but otherwise is 

 almost inactive. 



Substance III. Obtained by precipitating the filtrate (of the alcohol-soluble 

 oily fraction, after separation of substance II) with ether. This is gelatinous 

 and water-soluble, has about the same strength as the native venom. Requires 

 lecithin to be active. 



Substance IV. Precipitate obtained by treating the filtrate (the soluble portion 

 from which oily matter was removed by phenol) with alcohol. 



These bodies are called by Kyes incomplete lecithids, which differ from 

 the complete lecithid in their insolubility in alcohol. Of these four, sub- 

 stance II is neutralizable by antivenin, while some of the incomplete lecithids 

 remain unaffected. Complete lecithid is not reactive to antivenin, but is 

 said to be able to produce anti-serum, which neutralizes lecithid and native 

 venom equally. 



Snake venoms are not the only class of bodies which produce haemolysis 

 in the presence of lecithin. 



Pascucci ^ has shown that ricin becomes haemolytic when mixed with leci- 

 thin. Landsteiner and Jagic ^ discovered that the colloidal silicic acid, 

 which like ricin is usually only agglutinating, becomes upon the addition 

 of lecithin highly haemolytic. Landsteiner and Jagic explain this phenom- 

 enon as due to the adsorption of lecithin to the corpuscles previously or 

 simultaneously impregnated with the colloidal silicic acid. Naturally they 

 found that lecithin is by itself more or less haemolytic even without the inter- 

 mediation of this colloid. 



Later, Landsteiner and Jagic ' also found that the shaking of the mixture 

 of aqueous solution of colloidal hydrate of iron and choloroform solution of 

 lecithin gives rise to a new compound of these two bodies precipitable from 

 chloroform by a large quantity of ether. This relation is exactly what takes 

 place when venom and lecithin are shaken under the same conditions. 



Reiss * states that chloroform solution of lecithin can take up lac and trypsin 

 from aqueous solutions, but these ferments, which apparently had gone over 



• Pascucci. Ueber die Wirkung des Ricins auf Lecithin. Hofm. Beitr. zur chem. Physiol, u. Pathol., 



1906, VII, 457. t 



2 Landsteiner and Jagic. Ueber Analogien der Wirkung koUoidaler Kieselsaure mit den Reaktionen 

 der Immunkorper und verwandter Stofife. Wien. kUn. Woch., 1904, XVII, 63. 

 Landsteiner and Jagic. Ueber Reaktionen anorganischer KoUoide und Immunkorperreaktionen. 

 Miinch. med. Woch., 1904, LI, 1185. MichaeUs and Ehrenreich. Die Adsorptionsanalyse 

 der Fermente. Biochem. Zeitschr., 1908, X, 283. 



* Reiss. Eine Beziehung des Lecithins zu Fennenten. Berl. klin. Woch., 1904, XLI, 1185. 



