One female (KU 57156) having 230 ventrals and 54 caudals was found on the forest floor by day. This individual has a black snout with a white bar across the nasals and prefrontals, a white spot in the middle of the frontal, and a white band across the temporals and parietals that is bordered posteriorly by a black band. There are 28 white and 28 red rings on the body. The tips of the red scales are darkened. The black rings between the white and red rings are not so expanded as to interrupt the white rings dorsally as in _L. doliata abnorma_ as identified by Stuart (1948:70). Locally this snake, like all red, black, and white or yellow banded snakes, is called _coral_ or _coralillo_. =Leptodeira frenata malleisi= Dunn and Stuart Toocog, 1. This specimen, a male having 173 ventrals and 69 caudals, was found beneath the bark on a log in the forest. In life the dorsum was pinkish tan with 36 chocolate brown blotches on the body; the venter was rosy pink. =Leptodeira septentrionalis polysticta= Günther Chinajá, 3; Toocog, 11. If numbers of specimens are indicative of abundance, this is the most common snake in southern El Petén. All were found at night in the rainy season. At a pond in the forest at Toocog these snakes were observed on low vegetation, on the ground, and in the water. Evidently they congregate at breeding choruses of frogs. One _Leptodeira_ contained a _Smilisca baudini_ and another contained eggs of _Phyllomedusa callidryas taylori_. The natives call this snake _nahuyaca_. =Leptophis ahaetulla praestans= (Cope) 13 km. NNW of Chinajá, 1; 20 km. NNW of Chinajá, 1. Both specimens were obtained from trees when they were felled. One individual (KU 55716) has a body length of 1345 mm. and a total length of 2035 mm. In life the entire snake was uniform bright green; the eye was yellow. In preservative the dorsum is dark blue, and the venter is green. =Leptophis mexicanus mexicanus= Duméril, Bibron and Duméril Chinajá, 1; 15 km. NW of Chinajá, 1; Sayaxché, 4. All specimens came from low trees in the forest. The largest specimen is a male having a body length of 724 mm. and a total length of 1236 mm. In life the middorsum was a golden tan; the top of the head was a vivid green. One individual had ingested a _Smilisca baudini_. The local name is _bejuquillo_. =Ninia sebae sebae= (Duméril, Bibron and Duméril) Toocog, 1. This specimen, a male having 144 ventrals and 55 caudals, was found beneath bark on a log in the forest. There is a black band five scales in length on the nape followed posteriorly by a red band six scales in length and then by a complete black band one and one-half scales in length. The rest of the body is dull red with 16 incomplete black bands one to one and one-half scales in length on the anterior two-thirds of the body. =Oxybelis aeneus aeneus= (Wagler) Chinajá, 1; 20 km. NNW of Chinajá, 1.