TOL. Xni.] PHILOSOPHICAL TRANSACTIONS. 56l 



Vipera Caudisona ^mericanOj or the Anatomy of a Rattle-Snake^ dissected at 

 the Repository of the Royal Society in January l682-3. By Edward Tyson^ 

 M.D. Coll. Med. Lond. Cand. et R. S. Soc. N° 144, p. 25. 



The observations I shall here give are such as a single subject would afford, 

 not what might complete the history of so curious an animal. And though it 

 were mightily to be wished that we had an accurate account, and exact anatomy 

 of one of every distinct species of animals, yet this cannot be expected but of 

 those that are most common ; where frequent repeated dissections might fully 

 inform us of nature's admirable contrivance and mechanism of animal bodies. 



This which we dissected was sent to Mr, Henry Loades, a merchant in Lon- 

 don, from Virginia ; who was pleased not only to gratify the curiosity of the 

 Royal Society in showing it alive, but likewise gave it them when dead, and so 

 afforded an opportunity of farther satisfaction in observing the inward parts of 

 it; which I find so conformable in almost all respects to those of a viper, that I 

 have taken the liberty of placing it in that class, and (since it has not yet, that 

 I know of, any Latin name) of giving it that of vipera caudisona ;♦ for as I am 

 informed by merchants it is viviparous, and the epithet sufficiently distinguishes 

 it from those that have no rattle, although of these too there ought to be made 

 a subdivision. But I shall concern myself at present only with the anatomy, 

 which I think is yet given by none; though to me it seems the principal part in 

 a natural history of animals ; and for other accounts I shall refer to Marcgravius, 

 Piso, Johnston, Nierembergius, De Laet, Hernandez, and others who have 

 written of it; and describe it under the names of boiqininga, or boiqinininga, 

 and boiquira, which are the Brasil names. By the Portuguese it is called cas- 

 cavela and tangador; by the Dutch raetel-schlange ; by those of Mexico, 

 teutlacocauhqui, or teuhtlacot-zauhqui, i. e. domina serpentum, and from its 

 swift motion on the rocks like the wind, hoacoatl. 



Before we look within, we shall take a short survey of its outward parts. See 

 pi. 17. This that we dissected was 4 feet 5 inches long ; the girt of the body 

 in the largest place, which was the middle, was 6^ inches; the girt about 

 the neck 3 inches; near the rattle 2 inches; the head flat on the top, as 

 is the viper, and by the protuberance of the maxillae somewhat represent- 

 ing the head of a bearded arrow ; at the extremity of it were the nostrils, 

 (fig. 5, a), between them and the eyes, but somewhat lower, were two other 

 orifices (fig. 5, b), which I took for the ears, but after found they only led 

 into a bone that had a pretty large cavity, but no perforation. Vipers have not 



* The Linnaean generic name of the rattie-snake is crotalus. There are several species. 

 VOL. H. . 4 C 



