The _Solenoglypha_ are infinitely more formidable in the two divisions of the New World. They are represented by a large number of species, some of which are feared in consequence of their size and ferocity, even more than on account of the deadliness of their venom (fig. 67). [Illustration: FIG. 67.--HEAD AND SKULL OF _Crotalus horridus_.] The American CROTALINÆ are divided into two groups:-- The first of these comprises snakes not provided with the caudal appendage, which is characteristic of the Rattle-Snakes. It consists of two genera:-- (a) _Ancistrodon._ (b) _Lachesis._ The second group includes only those snakes the tails of which are terminated by the scaly appendage known as the “rattle.” These are likewise divided into two genera:-- (c) _Sistrurus._ (d) _Crotalus._ (a) =Ancistrodon.= Usually with 9 shields on the head, or internasals and præfrontals broken up into scales. Body cylindrical: scales smooth or keeled, with apical pits. Tail moderate or short; subcaudals single or in 2 rows. [Illustration: FIG. 68.--_Ancistrodon piscivorus_ (Water Viper). (After Stejneger.)] (1) _A. piscivorus_ (Water Viper, or Cotton-mouth; fig. 68).--Snout rounded, soft above. Scales on the body strongly keeled, in 25 (rarely 27) rows; 130-147 ventrals; 33-51 subcaudals, all single or the posterior divided. Colour pale reddish-brown to dark brown above, with more or less distinct dark brown cross-bands, or with alternating C-shaped dark markings each enclosing a central spot. Belly dull yellow spotted with black, or almost black. Total length, 1,170 millimetres; tail 200. _Habitat_: Eastern North America, from North Carolina and Indiana to Florida and Texas. The Water Viper lives for the most part in the vicinity of rivers, and feeds upon fish, but also devours small warm-blooded animals. The Creoles call it the Congo Snake. It is fairly common in the environs of New Orleans. In summer time it conceals itself in the branches of trees at the edge of the water. It frequents inundated rice-fields, and is a terror to the blacks. It attacks readily, and opens its jaws some seconds before it bites. (2) _A. bilineatus._--Snout obtusely pointed. Scales more or less strongly keeled, in 23 (rarely 25) rows; 135-141 ventrals; 52-64 subcaudals, anterior single, posterior divided. Colour dull yellow or reddish-brown, with more or less distinct darker cross-bands, or alternating transverse blotches, with yellow edges; a vertical yellow line on the rostral shield, and a fine yellow line round the snout; belly brownish or blackish, with white spots. Total length, 1,100 millimetres; tail 200. _Habitat_: Mexico, Guatemala, Honduras. (3) _A. contortrix_ (The Copperhead).--Snout rounded or truncate. Scales strongly keeled, in 23 (rarely 25) rows; 145-155 ventrals; 31-52 subcaudals, anterior single, posterior divided.