22. SYNOPSES AND DESCRIPTIONS. 
subtriangular or fused, sometimes displaced by the nasals. Scales keeled, 
except in Hydrops. 
Seales keeled; 
nasal divided ; 
teeth smooth in continuous series} 
loreal present TROPIDONATUS. 
loreal absent or present STORERIA. 
nasal grooved or divided; 
postmaxillary teeth larger and isolated 
HELICOPS. 
scales smooth; 
nasal grooved or divided; 
postmaxillary teeth little larger HYDROPS. 
TROPIDONOTUS. 
Kuhl, 1826. 
Stout to slender, tapering to head and tail, belly round; head distinct, 
crown flat, occipital tract broad, snout narrow; tail tapering to a point. 
Eye moderately large, pupil round. Teeth smooth and equal, or posterior 
a little larger. Head-shields normal, anterior small. Nasal in two parts, 
nostril between. Internasals small, narrowed anteriorly or triangular. 
A loreal. Preoculars 1—3. Postoculars 2—5. Suboculars present in 
T. cyclopium. Scales keeled, pointed, truncate or emarginate, in 17—83 
rows, outer broader. Subcaudals in two rows. 
Anal entire; 
series of rufous spots; rostral resembling that of Salvadora; series 
of scales 21 rufipunctatus. 
striped; series of scales 19 (17—19); slender saurita, 
striped and spotted; series of scales 17—21 sirtalis 
Anal bifid; 
banded transversely; series of scales 23—25 fasciatus. 
transverse bands and spots; series 29—31 taxispilotus. 
transverse bands to uniform; with suborbitals; series 27—33 
cyclopium. 
irregularly spotted; series 19—21 compressicaudus. 
spots in longitudinal rows; series 19 kirtlandii. 
striped; orbitals 2—2; series 19 leberis. 
