or Rattle-snake, in Zoology, a genus belonging to the order of amphibia serpentes. See Ophiology Index. The following is the account given by Mr Catesby of the crotalus horridus, or American rattle-snake. This grows sometimes to the length of eight feet, and weighs between eight and nine pounds. The colour of the head is brown; the eye red; the upper part of the body of a yellowish-brown colour, transversely marked with irregular broad black bands. The rattle is of a brown colour, composed of several horny, membranous cells, of an undulated pyramidal figure. These are articulated within one another in such a manner that the point of the first cell reaches as far as the basis of the protuberant ring of the third, and so on; which articulation, being very loose, gives liberty to the parts of the cells that are inclosed within the outward rings to strike against the sides of them, and so to cause the rattling noise which is heard when the snake shakes its tail. This is the most inactive and slow-moving of all the snakes, and is never the aggressor except in what it preys upon. The above gentleman is of opinion that no remedy is yet discovered for the bite of this animal. He had frequently access to see Indians bitten by it, and always thought that those who recovered were cured more through through the force of nature, or by reason of the lightness of the bite, than by the remedies used. He tells us, that the Indians know their destiny the moment they are bitten; and if the bite happens to be on any of the large veins, they apply no remedies, as knowing them to be entirely useless. He believes the reports of the fascinating power of this serpent, though he never had an opportunity of seeing it. See the articles Poison and Serpent.

Crotalys Træ in antiquity, a kind of morris dancers, admitted to entertainments, in order to divert the company with their dancing and playing on an instrument called crotalum, whence they had their name.