It is not easy to decide on the writer or traveller from whom we get the first mention of the rattlesnake, which has an extensive geographical range on both the American continents. It was undoubtedly some South American explorer early in the sixteenth century, and long before any settlement in the New World had been made by the English. In a rare old book, the first edition of which was published in London, 1614, viz. ‘_Samvel Purchas. His Pilgrimage in all Ages; being an account of all the Places discovered since the Creation of the World_,’ we hear of many Spanish and Portuguese authors who are but little known in England, and from each and all of whom the indefatigable ‘Pilgrim’ has culled information. Indeed, the book is a careful compilation from all the previous writers of any worth, though those only who mentioned the Brazilian serpents need be here introduced to the reader. These, in describing some unchanging peculiarities, and in giving us the vernacular names then common, have been of much use in assisting subsequent writers to identify certain species. Hakluyt, Hernandez, Master Anthony Kniuet, and many others are quoted by Purchas, but of them all, ‘No man hath written so absolute a Discourse of Brazil as was taken from a Portugall Frier and sold to Master Hakluit,’ he tells us; giving at the same time a history of the persecution and imprisonment of this unfortunate friar, whose unusual intelligence seems to have rendered him an object of suspicion. Thus do we who come after benefit by the misfortunes of our predecessors, and thus has the stolen ‘Discourse’ of the sixteenth century been turned to account for our edification in the nineteenth. In the Portuguese friar’s description of animals, it is not difficult to separate the true snakes from the ‘Serpentes with foure Legges and a Taile,’ or to identify the rattlesnakes among them. Says the writer, ‘The Boycininga is a Snake called of the Bell: it is of a great Poison, but it maketh such a Noise with a Bell it hath in its Tayle that it catcheth very few: though it be so swift that they call it the flying Snake. His Length is twelve or thirteen Spannes long. There is another _Boycininpeba_. This also hath a Bell, but smaller. It is blacke and very venomous.’ These two may be _Crotalus horridus_ and _Crotalus durissus_, the two commonest; or they may be only one species of a different size, age, and colouring—a confusion which frequently occurs with even more recent and more scientific worthies than the good ‘Pilgrim’ Purchas. In a later edition he says: ‘Other Serpents there are that carrie upon the Tippe of their Tayle a certaine little roundelle, like a Bell, which ringeth as they goe.’