100 OPHIDIA. 
RHINOCHIULUS. 
Rhinocheilus, Baird & Girard, N. Amer. Rept. p. 120 (1853). 
1. Rhinochilus lecontei. 
Rhinocheilus lecontei, Baird & Girard, 1. c.; Jan, Iconogr. Ophid. xlviii. t. 3. fig. 1 ; Bocourt, Miss. 
Sc. Mex., Rept. p. 602, t. 40. figg. 7, 7 a-e. 
Rhinocheilus lecontei, var. tessellatus, Garman, Mem. Mus. Comp. Zool. viii. no. 8, p. 73. 
Hab. Nortu America, Southern United States.—Muxico, Coahuila (Garman). 
Scales in twenty-three rows. 
2. Rhinochilus antonii. 
Rhinocheilus antonii, Dugés, Proc. Am. Phil. Soc. xxii. p. 86. 
Hab. Mexico, Mazatlan on the Pacific coast. 
Scales in seventeen rows. Ventrals 200; subcaudals 38 simple and 3 paired. 
LEPTOCALAMUS. 
Leptocalamus, Giinth. Ann. & Mag. N. H. 1872, ix. p. 16. 
The specimen on which this genus has been founded, Leptocalamus torquatus, is said 
to be from South America, and therefore cannot be included in this fauna. However, 
a second species has been described from Mexico, which Cope rightly supposes to belong 
to this genus. 
1. Leptocalamus unicolor. 
Geophis unicolor, Fisch. Abhandl. naturwiss. Ver. Brem. vii. p. 227, t. 15. figg. 1-3 (1880). 
Enulius murinus, Bocourt, Miss. Sc. Mex., Rept. p. 537, t. 35. figg. 9, 9a-g (nec Cope). 
Leptocalamus unicolor, Cope, Proc. Am. Phil. Soc. xxii. p. 178 (1885), and Bull. U. 8S. Nat. Mus. 
no. 32, 1887, p. 84. 
Geagras longicaudatus, Cope, Amer. Nat. 1884, p. 162. 
Hab. Mexico, Tehuantepec (Sumichrast). 
Habit very long and slender; head small, narrow, not distinct from neck; eye small, 
pupil round. Rostral shield broad; posterior frontals about thrice the size of the anterior ; 
vertical subtriangular, acutely pointed behind ; supraoculars of moderate size ; anterior 
ocular nearly as long as the two nasals together; two postoculars; seven upper labials, 
the third and fourth entering the orbit. Temporals 1+ 2. Scales in seventeen rows. 
Ventrals 203. Only one pair of chin-shields. Upper parts uniform brown, yellow 
below. 
Enulius sumichrasti, Bocourt, Miss. Sc. Mex., Rept. p. 538, t. 31. figg. 6, 6 a-c 
(Geagras sumichrasti, Cope, Amer. Nat. 1884, p. 162), does not appear to be specifically 
distinct from L. unicolor. 
