SYNOPSES AND DESCRIPTIONS. 95 
the dark color is produced toward the throat. On account of the amount 
of variation of this species in different localities, it is hardly to be separated 
from the preceding. Canada to Central America. 
sirtalis. Rows 19. Spots 70—90.  Ventrals 140—165+60—85 pairs. 
Mississippi Valley and eastward. 
15. Ventrals 145—175+50 
marcianus. Rows 21, Spots 50: 90 pairs. 
Texas to Mexico. 
parietalis. Rows 21. Spots 70—110. Ventrals 160—185 +50. 
Valley of the Missouri and westward. 
19. Spots 100—120. Ventrals 145—175+75 
pairs. California and northward. 
collaris. Rows 19. Ventrals 151—165+58—84 (Jan.) Mexico to Panama. 
ordinatus. Agrees with sirtalis, but has the lower series of spots more 
90 pairs. 
infernalis. Rows 17 95 
distinct, while the stripes are almost obsolete, and is found in various 
isolated localities of the same district, as Alabama, South Carolina, 
Martha’s Vineyard, and Nova Scotia. 
Troprponotus stpEpon, pl. IT, fig. 3. 
CotuBer stpepon Linné, 1758, Syst. Nat., ed. X, 219. 
Troprponorus strpepon Holbrook, 1842, N. A. Herp. IV, p. 6, pl. 29. 
Stout, fusiform, belly broad; head distinct, narrow forward: tail smaller 
than the body, tapering. Eye medium, pupil round. Mouth-cleft deep, 
abruptly curved near the angle. Nine head-shields. Rostral low, broader 
than high. Nasal in two parts, nostril between. A loreal. One anteor- 
bital, sometimes two. Postorbitals two to four. Temporals 1+2, large. 
Labials 8 (7—9), sixth and seventh large, Infralabials 10 (9—11), fifth 
and sixth large. Submentals two pairs, large, not in contact with the 
mental. Seales strongly keeled, in 23 to 25 rows, dorsal narrow, outer 
broader than long, keeled to smooth. Ventrals 130—155. Anal divided. 
Subcaudals 40—75 pairs. 
Varying from ashy to very dark brown, or to brownish-red; with three 
series of dark-edged brown spots; dorsal about ten scales in width, varying 
in shape from irregular rounded to nearly square, distinct or confluent with 
the lateral into transverse bands, which widen toward the vertebral rows. 
There are usually twenty-five to thirty spots on the flank, wider than long, 
and from fifteen to twenty on the tail. Commonly the spots on the flanks 
are more or less opposed and confluent anteriorly, but posteriorly alter- 
