_Remarks._--A precise diagnosis for _P. b. levipes_ is difficult to prepare because some geographic variation in color and in the cranial characters is present within the range of the subspecies as here understood. For instance there is a gradual cline of decreasing size to the northward in nearly all measurements, but the ratio of length of tail to length of head and body does not present such a cline; mice from several localities in San Luis Potosí have a relatively shorter tail than do mice from farther north and from farther south. Also, specimens labeled in reference to Zacualpilla, Jacales, Jacala, Tulancingo, and San Miguel Regla average slightly darker dorsally than do typotypes. Some of these specimens are reddish on the cheek and lateral line. Specimens from San Luis Potosí resemble topotypes, but some specimens from northeastern localities in that state have cinnamon or brownish upper parts and are intermediate in coloration between populations of _levipes_ to the south and populations of the same subspecies to the north from the Sierra Madre Oriental and the Sierra de Tamaulipas. Specimens from these two sierras have a cinnamon-reddish color that is more intense in specimens from the Sierra de Tamaulipas. Osgood (1909:153) recorded _P. b. levipes_ as occurring from central Nuevo León south through San Luis Potosí, Hidalgo, and Veracruz to southern Oaxaca. Actually specimens from Nuevo León and from most parts of Veracruz differ subspecifically from _levipes_ and also from each other. In Veracruz, _P. b. levipes_ is known only from the northwestern part. _Specimens examined._--Total 179 as follows: TAMAULIPAS: Sierra Madre Oriental, 5 mi. S, 3 mi. W Victoria, 1900 ft., 2; _8 mi. S, 6 mi. W Victoria, 4000 ft._, 37; Sierra de Tamaulipas, 2000 ft., 8 mi. S, 11 mi. W Piedra, 13. SAN LUIS POTOSI: Villar, 11 (USNM); 10 km. E Platanito, 19 (LSU); _8 mi. E (by road) Santa Barbarita_, 12 (LSU); _Agua Zarca_, 3 (LSU); 6 km. NE Cd. Maíz, 13 (LSU); _Pendencia Region (Puerto Lobos)_, 1 (LSU); _Pendencia, 2-1/2 mi. N Puerto Lobos_, 5 (LSU); 3 km. SW Sán Isidro, 15 (LSU); Cerro Coneja Region, Llano Coneja, 6100 ft., 2 (LSU); Xilitla, 4 (LSU). HIDALGO: 10 mi. NE Jacala, 5050 ft., 7; Regla (Sán Miguel), 2250 m., 4; Arroyo de las Tinajas, 2370 m., 9.5 km. SSW Tulancingo, 1; 10 mi. NW Apam, 7750 ft., 1. VERACRUZ: 3 km. N Zacualpan, 6000 ft., 1; _3 km. W Zacualpan, 6000 ft._, 12; _2 km. N Los Jacales, 7500 ft._, 8; _6 km. WSW Zacualpilla, 6500 ft._, 5. TLAXCALA: Mt. Malinche, 3 (USNM). #Peromyscus boylii beatae# Thomas 1903. _Peromyscus beatae_ Thomas, Ann. Mag. Nat. Hist., ser. 7, 11:485, May, type from Xometla Camp, Mt. Orizaba, Veracruz. _Geographic distribution._--East side of the Sierra Madre Oriental in Veracruz, from Jalancingo south to Xuchil.