188 REPORT OF NEW JERSEY STATE MUSEUM. 
Family CROTALIDE. 
The Rattle Snakes. 
Body stout. Head large, flat, triangular, and on a slender 
neck. Pupil elliptical, placed vertically. Maxillary vertical, 
without solid teeth, but provided with long erectile poison fangs, 
one on each side in front. A deep pit between eye and nostril 
extending into the excavated maxillary. Scales keeled in our 
species. Anal plate entire. Subcaudal plates generally undi- 
vided, at least anteriorly. ‘Tail usually provided with a rattle 
composed of modified horny rings. 
Viviparous serpents, attaining in some cases a large size, and 
renowned for their venom. All are American and comprise about 
a dozen genera. 
Key to the genera. 
a. Tail short, without rattle, ending in a horny point. AGKISTRODON 
aa. Tail with a rattle. CROTALUS 
Genus AGKISTRODON Beauvois. 
The Copper Head Snakes. 
Agkistrodon contortrix (Linnzus). 
PLATE 48. 
Copper Head Snake. Copper Head. Copper Belly. Copper 
Adder. Copper Viper. Copper Snake. Chunk Head. 
Deaf Adder. Rattle Snake’s Mate. 
Body robust, more or less ovoid in cross-section of trunk, with 
bulge a little below, and tapering but little or rather abruptly both 
anteriorly and posteriorly. Head small, well depressed, broad, 
and as viewed from above broadly ovoid or its greatest bulge 
about last 7% of its length. Snout broad, obtuse, upper surface 
flat, its sides more or less steeply and slightly converging below, 
