GENERAL PROPERTIES AND ACTIONS OF THE VENOM OF 

 HELODERMA, AND EXPERIMENTS IN IMMUNIZATION. 



BY ELIZABETH COOKE AND LEO LOEB. 

 (WITH SOME ADDITIONAL EXPERIMENTS BY MOYER S. FLEISHER.) 



REVIEW OF THE LITERATURE. 



The Gila monster is a reptile found in the southwestern portion of the 

 United States and also in Mexico. The Heloderma suspedum is usually found 

 in the United States; in Mexico the Heloderma horridum is more common. 

 The bite of either species is supposed to have a distinctly poisonous effect; 

 however, the general evidence in the literature regarding the toxic effects of 

 the venom of these animals is distinctly contradictory. The physiological 

 action of the venom has been studied by several observers: Sumichrast (Note 

 on the habits of some Mexican reptiles, Ann. and Mag. Nat. Hist., vol. 13 (3), 

 p. 497, 1864); Boulenger (Proc. Zool. Soc., London, 1882, p. 631); A. Duges 

 (Cinquantenaire de la Soc.de Biologie, Volume jubelaire, public par la Societe, 

 p. 134, Paris, 1899); Gorman (Bull. Essex Institute, Salem, Mass., vol. 22, 

 p. 60, 1890) ; and Boncourt (Compt. rend, de TAcad. des Sciences, vol. 80, p. 

 676, 1875). Boncourt caused animals of different species to be bitten by helo- 

 dermas and noted that the bite was fatal to smaller animals, such as frogs, 

 chickens, rabbits, and guinea-pigs, while dogs and cats developed serious sym- 

 toms, from which, however, they usually recovered. Besides these observa- 

 tions, there have been reported instances of more or less serious disturbances 

 arising from accidental injuries to human beings, but in regard to these the 

 evidence is very conflicting and appears to be scarcely trustworthy. 



Mitchell and Reichert (Medical News, vol. 42, p. 209, 1883; Science, 

 vol. 1, p. 372, 1883; Amer.Nat., vol. 17, 800, 1883) were the first to collect the 

 venom and to study in detail the symptoms produced by injecting it into ani- 

 mals in known quantities. They caused the helodermas to bite upon a saucer 

 edge and with the secretion thus obtained they made experiments upon frogs, 

 rabbits, and pigeons. Since that time several other investigators have col- 

 lected the venom and have investigated its properties. 



Santessoii (C. G. Santesson, Ueber das Gift von Heloderma suspectum 

 Cope, einer giftigen Eidechse, Nordiskt Medicinskt Arkiv. Testband tillegnadt 

 Axel Key, Nr. 5, 1897) obtained the poisonous secretion by causing animals to 

 chew upon small sponges, which he afterwards washed out with physiological 

 salt solution. The venom thus obtained he studied with reference to its chem- 

 ical constitution and with it also made a number of experiments on frogs, 

 rabbits, and mice. 



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