Cope] ^'^^ [July 16, 



Nine superior labials ; head long, swollen behind ; two loreals ; head 

 with a lyre-shaped pattern, back with irregular rhombs, with pale 

 centres ; tail one-sixth the length. T. lyrophakes. 



Nine superior labials ; head long ; two loreals ; head with chevron 

 bands ; body with irregular pale centred rhombs. 



T. BISCTJTATUS. 



Scales in 27 Bows. 

 Nine superior labials, three loreals ; head elongate ; two dark cross- 

 bands and two chevrons on head ; back with very irregular rhombs, with 

 pale centres ; tail one-sixth. t. major. 



Trimorphodon tau, Cope. 



Scales in twenty-three series. Muzzle projecting considerably beyond 

 the mouth. Rostral plate somewhat produced behind ; inteniasals, 

 about one-fourth size of prefrontals, which are long as wide. Frontal 

 with straight lateral margins, which are longer than anterior. Occipital 

 not longer than frontal, regailarly rounded behind. Nostril in middle of 

 nasal. Three loreals, three post and three preoculars. Temporals, 2-3-4. 

 Superior labials six, the fifth probably composed of two plates fused, as 

 it is twice as long as deep, on both sides. The fourth and fifth enter the 

 orbit, the third is cut down by the lower loreal and preocular. Inferior 

 labials, eleven. Body strongly compressed. Total length Om. 236 ; of 

 tail, .035 m. 



Above gray, with twenty-three jet-black rhombs, which extend to the 

 gastrosteges by their lateral angles. Tail with ten rhombs ; all every- 

 where unspotted with paler. Sides of belly black spotted. Head gray 

 with a black mask above as far as the middle of the occipitals, but with 

 two lateral ear-shaped prolongations on the same ; a pale T-shaped mark 

 extends transversely between orbits, and longitudinally to end of 

 ntiuzzle. 



One specimen, No. 236, from F. Sumichrast, from the western part of 

 the Isthmus of Tehuantepec, Mexico. 



Trimophordon upsilon. Cope. 



Internasals broader than long, prefrontal broad as long, frontal with 

 parallel outline not reached by the preocular. Oculars 3-3. Nasals dis- 

 tinct, loreals three, forming an L. Temporals 3-3-3. Fourth and fifth 

 labials in contact with orbits. Twelve inferior labials. Scales in 2-3 

 series. Body with twenty-four brown annuli, which are broken into 

 irregular spots on the belly, and are broader than long on the vertebral 

 line. On all but the anterior third the length, a vertical brown bar stands 

 between these on the sides. Chin and lips white, superior plates brown 

 spotted above. Loreal region spotted. Temporal and occipital region 

 brown with a pale Y on the occipital common suture. Total length 

 0.34 m. Tail .052 m. ; head to aictus .011 m. 



One specimen in Mus. Smithsonian from I. I. Major, from Guadalaxara, 

 West Mexico. 



