Ticul Alvarez

“ Therefore, Osgood in 1909 in his revision of the genus Peromyscus reported only two subspecies of P. boylii from eastern México: P. b. levipes, and P. b. aztecus. Study of Osgood's and Thomas' material, along with recently collected specimens from the states of eastern México, leads me to conclude that P. aztecus and P. boylii are different species; that P. beatae is a valid subspecies different from P. b. levipes; and finally that specimens of P. boylii from Nuevo León and northwestern Tamaulipas pertain to an hitherto unnamed subspecies.
Peromyscus aztecus Saussure
1860. ”

“ 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 [Pg 116] cline; mice from several localities in San Luis Potosí have a relatively shorter tail than do mice from farther north and from farther south. ”

“ Mount Malinche (type locality of levipes) , and Thomas had not compared beatae with levipes. Xometla, on the east side of the Volcán de Orizaba, is approximately 56 miles east of the Tlaxcalan part of Mount Malinche and is situated where the Tropical Life-zone begins, whereas Mount Malinche is in the Austral Life-zone on the Mexican Plateau; the difference in habitat between the two places is great. Topotypes of levipes differ from two topotypes of beatae in the same fashion as do other specimens of levipes (from San Luis Potosí) from other specimens of beatae (from Veracruz) . ”