Records of occurrence.—Specimens examined, 101: 7 km. SW La Purisima, 1; Sierra Madre Oriental, 5 mi. S, 3 mi. W Victoria, 1900 ft., 12; Sierra Madre Oriental, 8 mi. S, 6 mi. W Victoria, 4000 ft., 16; Sierra de Tamaulipas, 2 mi. S, 10 mi. W Piedra, 1200 ft., 36; Sierra de Tamaulipas, 3 mi. S, 14 mi. W Piedra, 1200 ft., 14; 14 mi. N, 6 mi. W Palmillas, 5500 ft., 1; Palmillas, 4400 ft., 3; 53 km. N El Limón, 12 km. S Río Guayalejo, 5; Joya Verde, 35 km. SW Victoria, 3800 ft., 9; 10 km. N, 8 km. El Encino, 400 ft., 1; 8 km. NE Antiguo Morelos, 500 ft., 3.
Additional records (Hooper, 1952:374, unless otherwise noted): Sierra San Carlos (Marmolejo, 1700 ft., San José, 2000 ft., Tamaulipeca, 1500 ft., La Vegonia, 2900 ft.); Villagran, 1300 ft.; Cd. Victoria; near Jaumave, 2400 ft.; Sierra de Tamaulipas, near Acuña, 1600 ft.; La Joya de Salas (Goodwin, 1954:12).
Peromyscus pectoralis eremicoides Osgood
1904. Peromyscus attwateri eremicoides Osgood, Proc. Biol. Soc. Washington, 17:60, March 21, type from Mapimi, Durango.
1909. Peromyscus pectoralis eremicoides, Lyon and Osgood, Bull. U. S. Nat. Mus., 62:128, January 28.
Distribution in Tamaulipas.—Known only from Miquihuana and vicinity of Tula.
The two specimens from Miquihuana are typical P. pectoralis eremicoides in external and cranial measurements. Specimens from nine miles southwest of Tula are characteristic of eremicoides in cranial measurements but the tail is shorter than usual for this subspecies, in this respect approaching P. p. lacianus.
Measurements.—Average and extreme measurements of 10 specimens from nine miles southwest of Tula and measurements of two males (56169, 56415) from Miquihuana are, respectively, as follows: 181.5 (173-197), 180, 197; 96.2; (87-110), 103, 113; 20.2 (19.0-21.5), 21, 21; 18.1 (16.5-19.0), 18, —; greatest length of skull, 24.8 (24.1-25.6), 25.5, 25.6; length of nasals, 9.0 (8.6-9.3), 9.3, 9.3; zygomatic breadth, 12.2 (11.7-12.8), 12.3, 12.9; interorbital constriction, 3.8 (3.7-4.0), 3.7, 3.9; length of maxillary tooth-row, 3.6 (3.5-3.7), 3.6, 3.8. Weights of the 10 specimens from nine miles southwest of Tula average 17.9 (16-24) grams.
Records of occurrence.—Specimens examined, 28: Miquihuana, 6200 ft., 2; Nicolás, 56 km. NW Tula, 5500 ft., 1; Tajada, 23 mi. NW Tula, 5200 ft., 1; 8 mi. N Tula, 4500 ft., 2; 9 mi. SW Tula, 3900 ft., 19; 17 mi. SW Tula, 3900 ft., 3.