There are several varieties of grasshopper mice (Orychomys), white-footed mice (Peromyscus), harvest mice (Reithrodontomys), rice-rats (Oryzomys), wood-rats (Neotoma), voles (Microtus), &c. Bats inhabit caves in Burnet, Williamson, Lampasas, Gillespie and other counties.
Both in size and form considerable variability is displayed, the species of Holochilus being some of the largest, while the common white-footed mouse (Eligmodon leucopus) of North America is one of the smaller forms. Some kinds, such as Oryzomys and Peromyscus have long, rat-like tails, while others, like Acodon, are short-tailed and more volelike in appearance.
The Florida rice-rat (Sigmodon hispidus) is another well-known representative of the group. In the Old World the group is represented by the Persian Calomyscus, a near relative of Peromyscus.
Persia is the home of Calomyscus (with one species), a near relative of the American Peromyscus.