145. , TBIMOKPHODON. 55 



i. c? (Sc. 25 ; V. 251 ; Lanquin, Guatemala. 0. Salvin, Esq. [C.]. 



0. 87). 

 k. Hgr. ? (Sc. 27 ; V. Guatemala. 0. Salvin, Esq. [C.]. 



253; 0.81). 

 I. S (Sc. 27 ; V. 263 ; Nicaragua. 



C. 79). 

 S t? (Sc. 25; v. 259; Panama. Capt. J. 0. Dow [P.]. 



■ 0.89). 

 n. Hgr. $ fSc. 26 ; V. 0. America. Haslar Collection. 



256; 0.77). 

 0. Skull. SanKamon, Mexico. Dr. A. 0. BuUer [0.]. 



2. Trimorphodon upsilon. 



Trimorphodon upsilon, Cope, Froc, Amer. Philos. Soo. xi. 1869, 



p. 152, and xxiii. 1886, p. 286; Gunth. Biol. C.-Am., Rept. p. 175 



(1895). 

 Dipsas biscutata, var. latifascia, Peters, Mon. Berl. Ac. 1869, p. 877. 

 Eteirodipsas biscutata, Jan, Icon. 64n. 89, pi. i. fig. 3 (1872). 

 Trimorphodon coUaris, Cope, Joum. Ac. Philad. (2) viii. 1876, p. 131, 



and 1^00. Amer. Philos. Soc. xxiii. 1886, p. 286. 

 Sibon biscutatum, part., Oarm. N. Am. Rept. p. 16 (1883). 



upsilon, Garm. I. c. p. 134. 



? Trimorphodon vilkinsonii, Cope, Proa. Amer. Philos. Soc. xxiii. 



1886, p. 285. 



Eostral broader tban deep, the portion visible from above 

 measuring one fourth to one third its distance from the frontal ; 

 internasals much shorter than the prsefrontals, ■which are nearly as 

 long as broad ; frontal once and a half to once and two thirds as 

 long as broad, as long as or a little longer than its distance from the 

 end of the snout, as long as the parietals ; two or three loreals ; 

 two praeoculars and a subocular ; upper prseoeular in contact with 

 or narrowly separated from the frontal ; two or three postoculars ; 

 temporals 2+2, 2 + 3, or 3+3 ; eight or nine upper labials, fourth 

 and fifth entering the eye ; five or six lower labials in contact 

 with the anterior chin-shields, which are longer than the posterior. 

 Scales in 21 or 23 rows. Yentrals 205-236 ; anal divided ; sub- 

 oaudals 61-72. Pale grey-brown above, with dark, black-edged 

 cross-bars narrowing on the sides and descending to the ends of the 

 ventrals; head dark brown above, pale greyish on the occiput, 

 usually with a light cross-bar between the eyes ; a V-shaped light 

 marking sometimes present on the parietal shields, embracing the 

 frontal ; whitish beneath, more or less mottled with dark and with 

 dark spots on the sides. In the young the dark bars are much 

 wider, separated by narrow whitish interspaces, and they may form 

 complete annuli. 



Total length 660 millim. ; tail 120. 



Mexico. 



a. 3 (Sc. 23; V. 217 ; La Cumbre de los Dr. A. 0. BuUer [0.]. 



0. 71). Arrastrados, Jalisco. 



5. 2 (Sc. 21 ; V. 205 ; Jalapa. Mr. Hoege [0.]. 



C. 61). 



