MEMOIR ON AMPHIBIA. i)^;^ 



Before I enter into the detail of my obfervations, it is 

 neceffary to prefent and difcufs fuccindlly, what has been 

 iaid and written on thefe animals, and to examine what 

 we know concerning them. 



The manner in which thefe amphibia attack the animals 

 dehined for their food is one of thofe problems in natural 

 hiftory which are yet to be refolved. The means they 

 employ, as well as the real caufes of many furprlfmg eSe£ls, 

 not yet well or unanimoufly flated, are imknown to us. 

 According to fome, the crotali and feveral other fcrpents 

 have the faculty of enchanting and actrafting birds, fquir- 

 rels, rabbits, frogs, &c. (aves fciurofque ex arboribus in 

 fauces revocant. Linn. Syft. Nat.) According to others 

 they infpire them with terror, to fuch a degree, that if we 

 can put faith in the effed:s related, we fliould be tempted 

 to believe that they are from that moment deprived of 

 their fenfes, and, as it were, attacked with inianity. Ac- 

 cording to others, in fine, thefe animals are violently af- 

 fected and fuffocated by a vapour, and fetid emanation, 

 which the reptile difFufes upon every thing around it. 



It is faid that when the ferpent wifhes to feize a bird, a 

 fquirrel, &c. he remains motionlefs, his eyes coaftantly 

 fixed upon his prey, and that then the unhappy vidim, 

 adled upon by a fupernatural power, lofes all its faculties, 

 and cannot even have recourfe to flight : it agitates itfelf, 

 throwing out lamentable cries, goes, returns, advances, 

 retreats, approaches, retires, comes and goes again, till 

 at laft exhaufted by fatigue, it voluntarily delivers itfelf up 

 to its enemy, who delays not to devour it. Such are the 

 efFedls attributed to enchantment, terror, or the fuffocating 

 vapour which thofe ferpents, it is faid, have the power of 

 cafting round them, and which afFeds every animal which 

 is found within its atmofphere. Let us examine thefe 

 three pretended caufes, and compare them with their fup- 

 pofed efFeds. 



3 B 2 Admitting 



