CONOPSIS. 97° 
The snakes of this genus are not strictly isodont. The posterior teeth are always 
somewhat stouter, if not longer than the anterior, which is particularly conspicuous 
in specimens exceeding ten inches in length. In specimens of that size sometimes a 
distinct elongate pit at the base of the tooth may be seen, apparently the commence- 
ment of a groove. Therefore Conopsis might be regarded as a less developed form of 
Stenorhina. 
The nasal shield is invariably single; but the frontal shields may be a single or 
double pair in specimens from the same locality and apparently of the same brood. 
1. Conopsis nasus. (Tab. XXXIV. figg. B-B".) 
«. Synonymy of specimens with a single pair of frontal shields :— 
Conopsis nasus, Giinth. Col. Sn. p. 6; Bocourt, Miss. Sc. Mex., Rept. p. 568, t. 35. figg. 2, 2 a-d. 
Ficimia nasus, Garman, Mem. Mus. Comp. Zool. viii. no. 3, p- 83 (1883) 
Oxyrhina (Exorhina) maculata, Jan, Arch. per la Zool. ii. p. 61 (1862). 
Ficimia maculata, Garman, Mem. Mus. Comp. Zool. viii. no. 3, p. 84, 
Conopsis maculatus, Bocourt, Miss. Sc. Mex., Rept. p. 564, t. 35. fig. 3. 
8. Synonymy of specimens with two pairs of frontal shields :— 
Oxyrhina varians, Jan, Arch. per la Zool. ii. p. 60 (1862). 
Conopsis varians, Bocourt, Miss. Sc. Mex., Rept. p. 566, t. 35. figg. 5, 5 a-d. 
Ogmius varians, Cope, Proc. Am. Phil. Soc. 1869, p. 162; and Proc. U. S. Nat. Mus. ix. p. 189 
(1887). 
Conopsis nasus, Peters, MB. Ak. Wiss. Berl. 1869, p. 875. 
Conopsis lineatus, Bocourt, Miss. Sc. Mex., Rept. p. 565, t. 35. tigg. 4, 4a-d (nec Toluca lineata, 
Kenn.). 
Chionactis diasit, Cope, Proc. U. S. Nat. Mus. ix. p. 188 (1887). 
Ogmius acutus, Cope, Proc. U. S. Nat. Mus. ix. p. 189 (1887). 
Hab. Nort America, California (Mus. Brit.)—Muxico (Sailé), Milpas in Durango 
(forrer), Omilteme in Guerrero (H. H. Smith), La Cumbre de los Arrastrados 
(Buller), Puebla (Peters), Tehuantepec (Sumichrast). 
This species is subject to a considerable amount of variation; the small scutes of 
the head, such as the loreal, postoculars, and labials, frequently disappear by coalescence. 
The ground-colour may be light buff or dark brownish grey, uniform or with dark spots 
of variable size and shape. The lower parts may be uniform whitish, or varied with 
more or less numerous subquadrangular black spots; sometimes there is a black median 
subcaudal line. Even the physiognomy varies, the snout being in some specimens 
more obtusely rounded than in the type. 
Several illustrations of the head, of twice the natural size, are given to show the 
extraordinary variations of its shape and of the scutes—fig. B representing the typical . 
specimen from California; fig. B’ that from Milpas, B" one from Sallé’s Mexican 
collection, and B" one from La Cumbre de los Arrastrados. 
BIOL. CENTR.-AMER., Rept., August 1893. *13 
