1901.] NATURAL SCIENCES OF PHILADELPHIA. 493 



In the type specimen, which is adult, the head is broad, flat on 

 top and distinct from the neck, which is rather slender; the body 

 is stout and the tail a little less than one-eighth of the total 

 length. 



Rostral nearly twice as broad as high, barely visible from above, 

 luternasals narrow in front, half the length of prefrontals. One 

 pair of pi'efrontals. Frontal rather broad behind, one-third longer 

 than ils greatest breadth, the anterior corners cut ofi^ to form an 

 oblique suture with the preocular. Suture between the parietals 

 equals the length of the frontal, or the distance between the frontal 

 and rostral. Two large nasals, the nostril between them, situated 

 high up and directed rather upward. Loreal longer than high, 

 its upper border sloping downward and backward. One large 

 preocular, reaching the frontal. In each of the specimens a row 

 of two or three small accessory plates more or less completely sepa- 

 rates the eye, the preocular and the hinder end of the loreal from 

 tne labials, but they present variations in detail. The type has 

 9 upper labials on one side, and there are three accessory plates, the 

 first lying on the 3d and 4th, the second on the 4th and 5th, and 

 the third on the 5th labial; ou the other side there are 11 labials, 

 the first accessory lying on the 4th and 5th, the second on the 5th 

 and 6th, and the third on the 6th, the labials being wholly ex- 

 cluded from the orbit ou both sides. The largest of the smaller 

 specimens has 10 labials on each side, and the accessory plates are 

 as in the type. In the third specimen there are 11 labials on each 

 side, on one of which only the two anterior accessory plates are 

 present, and the sixth labial enters the orbit behind them; on the 

 other side, the 6th labial also reaches the eye, and all three 

 accessory plates are present, but the two hinder are small and are 

 pushed forward. In the smallest specimen the labials on one side 

 are 10, the first and second accessory plates only are present, 

 permitting the fifth labial to enter the eye; ou the other side, the 

 labials are 11, and the three plates completely shut out the 

 labials, as in the type and the second specimen. Three postocu- 

 lars, the inferior extending forward under the eye. The temporals 

 are small and irregular, from 3 to 5 in the first row. Lower 

 labials 14, the hinder ones small and scale-like. Five lower 

 labials in contact with the anterior chin shields; the hinder pair 

 shorter and widely separated. 



