198 REPTILIA: OPHIDIA. — XXVIII. 
presses and expands the head, hissing and threatening, but it is 
perfectly harmless. (mAarus, flat; pis, nose.) 
aa. Vertical plate encircled by 5 to 10 small plates. 
576. H. simus (L.). Hoag-nosep Snake. Dorsal blotches 
about 35; ground color usually pale yellowish brown; vertical 
plate much longer than occipitals, broader than long. V. P. 115 to 
150. Scales usually 25. Ill. and Wis. to S. C., chiefly S. (Lat., 
flat-nosed.) 
Famity CXI. HLAPIDAK. (Tue Harvequin SNAKES.) 
Venomous snakes, provided with two or more permanently erect, 
perforated fangs in the upper jaw, and usually a series of smaller 
teeth behind them; scales not keeled; head usually quadrangular, 
with flat crown and short muzzle; no loral plate. Genera 3, species 
about 20, chiefly East Indian, a few inhabiting the warmer parts of 
America. 
a. Anal plate entire; sub-caudal plates two-rowed ; two nasal plates; inter- 
nasal plate touching the nasal laterally. . . . . . . Ears, 289. 
289. ELAPS Schneider. (Old name of some snake.) 
577. EH. fulvius (L.). Brap Snake. Jet black, with about 
17 broad crimson rings, each bordered with yellow, and spotted 
below with black; a yellow occipital band; tail with yellow rings. 
V. P. 200 to 215. U. 32. Scales, 15 rows. L.30. Va. to Ark. 
and S. A beautiful snake, apparently harmless, although provided 
with venom-fangs. Resembles Zampr. doliatus. (Lat., reddish- 
yellow.) 
Famity CXII. CROTALIDAN. (THe RarttiesnaxEs.) 
Maxillary vertical, without solid teeth, but provided with long, 
erectile, perforated poison-fang on each side in front; a deep pit 
between eye and nostril, extending into the excavated maxillary. 
Body stout; head large, flat, triangular, on a slender neck; pupil 
elliptical, placed vertically. Tail usually provided with a rattle 
composed of horny rings, modified scales. Subcaudal plates gen- 
erally undivided, at least anteriorly. Scales keeled, in all our 
species; anal plate entire. Genera 12; species about 60, all Ameri- 
can, renowned for their venom. All are viviparous. 
a. Tail short, without rattle, ending in a horny point; top of head with about 
8 symmetrical plates arranged around the vertical plate; tail not pre- 
hensile. . 6 « «© © « «© + © « « «© « « AGKISTRODON, 290. 
aa. Tail with a rattle. 
6. Top of head with about 8 plates symmetrically arranged ; rattle small. 
SisrRuRvs, 291. 
6b. Top of head covered with small scales; rattle large. CRora.us, 292. 
