The range of _Leptodeira splendida bressoni_ apparently does not overlap that of _Leptodeira maculata_; the latter is restricted to the lower reaches of the arid scrub forest, whereas _L. s. bressoni_ inhabits the upper limits of the arid scrub forest and the lower part of the pine-oak forest. Specimens have been collected between 950 and 1630 meters on the slopes of the Cordillera Volcánica and at 950 meters in the Sierra de Coalcomán. At Uruapan individuals were found beneath rocks along a stream and in a stone fence. _Leptodeira duellmani_, which was described from Coalcomán by Peters (1954:25), is an aberrant individual of _L. s. bressoni_ (Duellman, 1958a:56). ~Leptophis diplotropis~ (Günther) _Ahaetulla diplotropis_ Günther, Ann. Mag. Nat. Hist., ser. 4, 9:25, 1872.--Tehuantepec, Oaxaca, México. _Leptophis diplotropis_, Bocourt, Mission scientifique au Mexique et dans l'Amerique Centrale, Reptiles, livr. 15:835, 1897. Between Aguililla and Dos Aguas; Arteaga; Coalcomán; El Diezmo; El Sabino (5); La Playa; Ocorla. Most specimens of this species have been collected in tropical semi-deciduous forest at elevations of less than 1000 meters. In the Sierra de Coalcomán one was taken in pine-oak forest at an elevation of 1700 meters near Ocorla; another was found in broad-leafed forest between Aguililla and Dos Aguas at an elevation of 1600 meters. Most individuals have been seen in trees or bushes. The absence of broad-leafed forest in the Tepalcatepec Valley probably accounts for the absence of this snake in that area. ~Manolepis putnami~ (Jan) _Dromicus putnami_ Jan, Elenco sistematico degli Ofidi, p. 67, 1863.--San Blas, Nayarit, México. _Manolepsis putnami_, Smith and Taylor, Bull. U. S. Natl. Mus., 187:92, October 5, 1945. La Placita (3); Maquili; Ostula. In Michoacán the species has been found only in tropical semi-deciduous forest on the lower slopes of the Sierra de Coalcomán. From the observations made by Peters (1954:28), this snake is diurnal and feeds on teiid lizards. ~Masticophis striolatus striolatus~ Mertens _Coluber striolatus_ Mertens, Zoologica (Stuttgart), 32:190, 1934.--Substitute name for _Coluber lineatus_ Bocourt, a secondary homonym of _Coluber lineatus_ Linnaeus = _Lygophis lineatus_. Type locality restricted to Presidio de Mazatlán, Sinaloa, México, by Smith and Taylor (1950a:343). _Masticophis striolatus striolatus_, Zweifel and Norris, Amer. Midl. Nat., 54:242, July, 1955. Apatzingán (4); Arteaga; Coalcomán (3); El Sabino; Jiquilpan; La Palma; La Playa (3); Lombardia; Nueva Italia; Río Cachán; Santa Ana; Uruapan (2); Volcán Jorullo; Ziracuaretiro.