|
|
|
Fig. 251.—Sternum and sternal ribs of the Common Mole (Talpa europaea), with the clavicles (cl) and humeri (H); M, Manubrium sterni. Nat. size. (From Flower's Osteology.) |
Fig. 252.—Bones of fore-arm and manus of Mole (Talpa europaea). × 2. C, Cuneiform; ce, centrale; l, lunar; m, magnum; p, pisiform; R, radius; rs, radial sesamoid (falciform); s, scaphoid; td, trapezoid; tm, trapezium; U, ulna; u, unciform; I-V, the digits. (From Flower's Osteology.) |
tributed as regards genera; a Mole just gets over the boundary into the Oriental region. The genus Talpa is entirely Old World in range, and includes several species, of which the Common Mole, T. europaea, is the best known. There are forty teeth, one of the molars of the full mammalian dentition not being represented. In the milk dentition there is an additional premolar, not represented by a successor in the permanent dentition. The formula is thus I 3/3 C 1/1 Pm 4/4 M 3/3. There are no external ears, and the eyes are rudimentary; the soft silky fur is familiar to everybody. The sternum has a strong crest, associated with a powerful development of the pectoral muscles, so necessary to a burrowing animal. The animal, it is hardly necessary to state, lives underground in burrows excavated by itself, which have not, it has been stated, the elaborate and, it appears, fanciful shape assigned to them by many writers. At times Moles appear above ground.
