_Variation._--Throughout the range of this subspecies the posterior body-blotches are brown and noticeably lighter than the anterior ones. Juveniles are colored like adults. Specimens from the northern part of the range (Nuevo León and Tamaulipas) have 21 to 28 (average 24.0) dorsal body-blotches and 7 to 11 (average 8.9) scales in the interspace between the first and second dorsal body-blotches, as compared with specimens from the southern part of the range (Hidalgo, Queretaro, and San Luis Potosí), which have 24 to 31 (average 27.7) dorsal body-blotches and 6 to 10 (average 7.8) scales in the first interspace. Likewise, there is a difference in the number of ventrals between the northern and southern samples; those from the north have an average of 228.8 ventrals, and those from the south have 222.0. In all of these characters the southern sample shows trends towards the southern subspecies, _deppei_, which has fewer ventrals, fewer scales in the first interspace, and more dorsal body-blotches. _Distribution._--Eastern part of the Mexican Plateau and lower leeward slopes of the Sierra Madre Oriental from Hidalgo and Queretaro northward to southeastern Coahuila. _Specimens examined._--Total of 28, as follows: _Coahuila_: Buena Vista, USNM 1522; 50 km. W of La Rosa, EHT-HMS 5374. _Hidalgo_: Ixmiquilpan, USNM 110890-1; 24 km. S of Ixmiquilpan, EHT-HMS 5373; Jacala, UMMZ 80937; 35 km. E of Pachuca, UMMZ 99552; 16 km. E of Tulancingo, KU 40357. _Nuevo León_: Ojo de Agua near Galeana, CNHM 33564-5. _Queretaro_: Cadereyta, UMMZ 99791-3. _San Luis Potosí_: Charcas, UMMZ 77256-8; San Diego, UMMZ 77254-5; 24 km. NE of San Luis Potosí, UIMNH 18711; 30 km. NE of San Luis Potosí, UIMNH 27150, 28135. _Tamaulipas_: Miquihuana, MCZ 19544-50. =Pituophis lineaticollis lineaticollis= Cope, new combination _Arizona lineaticollis_ Cope, Proc. Acad. Nat. Sci. Philadelphia, p. 300, 1861. _Pituophis lineaticollis_, Stull, Occas. Papers Mus. Zool. Univ. Michigan, no. 250, p. 2, October 12, 1932, Bull. U. S. Natl. Mus., no. 175, p. 47, April 23, 1940. _Pituophis deppei lineaticollis_, Smith, Proc. U. S. Natl. Mus., vol. 93, p. 460, 1943; Smith and Taylor, Bull. U. S. Natl. Mus., no. 187, p. 108, 1945. _Pituophis deppei brevilineata_ Schmidt and Shannon, Fieldiana-Zool., vol. 31, p. 79, February 20, 1947.