Voles, as typified by the water-rat and the tailed fieldmouse, are stouter built and shorter-nosed rodentsthan the typical rats and mice, with smaller ears and eyes and shorter tails; all being good burrowers.
The third sub-family is that of the Microtinae, or voles, which are distributed all over Europe, Northern Asia and North America, and are characterized by the tympanic bulla of the skull being filled with honey-combed bony tissue, the small size of the infra-orbital foramen, and the deep pterygoid fossa on the palatal aspect.
Various species of small native mice and voles are abundant.
The reindeer, arctic fox (Canis lagopus), hare, wolf, lemming (Myodes obensis), collar lemming (Cuniculus torquatus) and two species of voles (Arvicolae) are the most common on land.
Admixture of Mongolian species, such as Canis corsac, Felis manul, Spermophilus dauricus, the jerboa (Dipus jaculus), two hamsters (Cricetus songarus and C. furunculus), three new voles (Arvicolae), the Tolai hare, Ogotona hare (Lagomys ogotona), Aegocerus argali, Antilope gutturosa and Equus hemionus (jighitai).
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.
In most species the penis (which is generally provided with a bone) may be more or less completely retracted within the fold of integument surrounding the vent, and lie curved backwards upon itself under cover of the integument, or it may be carried forward some distance in front of the anal orifice, from which, as in voles and marmots,.
Although the British representatives of this group should undoubtedly retain their vernacular designations of water-rat and short-tailed field-mouse, the term "vole" is one of great convenience in zoology as a general one for all the members of the group. Systematically voles are classed in the mammalian order Rodentia, in which they constitute the typical section of the subfamily Microtinae in the Muridae, or mouse-group. As a group, voles are characterized by being more heavily built than rats and mice, and by their less brisk movements.
In common with lemmings and other representatives of the Microtinae, voles are, however, broadly distinguished from typical rats and mice by the structure of their three pairs of molar teeth.
On the number and relations of these prisms the voles, which form an exceedingly large group, ranging all over Europe and Asia north of (and inclusive of) the Himalaya, and North America, are divided into genera and subgenera.
Fossil voles from the Pliocene of England and Italy with molars which are rooted as soon as developed form the genus Mimomys.
Caudatus) live at the foot of the mountains, as well as four species of Spermophilus, three of voles, two of the mouse and three of the hamster.
It is true indeed that in zoological nomenclature some of these are distinguished as "voles," but this is not in accord with popular usage, where such creatures - come under the designation either of water-rats or field-mice.
Saxatilus), two voles (Arvicola russatus and A.
It is the home of the Columbia black-tail deer, western raccoon, Oregon spotted skunk, Douglas red squirrel, Townsends chipmunk, tailless sewellel (Haplodcn rufus), peculiar species of pocket gophers and voles, Pacific coast forms of the great-horned, spotted, screech and pigmy owls, sooty grouse, Oregon ruffed grouse, Stellers jay, chestnutbacked chickadee and Pacific winter wren.
Minutus), four voles (Arvicola amphibius, A.