| OCR Text |
Show 1885.] DR. ST. G. MIVART ON THE ARCTOTDEA. 379 To the cranial characters mentioned by Prof. Flower1 may be added the small length of the muzzle compared with the great length of the cranium proper. The infraorbital foramen is rather large, the zygomata delicate but well arched outwards, and the palate is prolonged backwards behind the last molars. The angle of the mandible, though much pressed upwards, is still distinctly distinguishable. Molar formula = P. \, M . j. The dentition is more sectorial than heretofore. The second upper and lower premolars are two-rooted. The fourth upper premolar has a very small hinder lobe, and no lobe in front of the principal lobe, so that the tooth is very like the corresponding one of Canis, especially as the internal lobe is anterior in position, opposite the front part of the principal cusp. Of the lower teeth, the front premolar is like that of Galictis. The first molar like that of Mellivora, but larger and especially lower, while the second molar is a small rounded tooth. The brain 2 shows a distinct but small Ursine lozenge in front of a considerable crucial sulcus which is placed rather far back. The sagittal gyrus is much the widest of the three circumsylvian gyri. The crucial and calloso-marginal sulci run one into the other. The Sylvian fissure is oblique and relatively long. Putorius3.-This very large genus of small-sized mammals is very wide spread, inhabiting as it does not only the Nearctic and Palaearctic regions and the Indian Archipelago, but also Africa, north and south, and South America, including Brazil. There may be something like two dozen species. The body attains its maxim u m of length and the limbs their minimum. Here for the first time we meet with species (P. vulgaris and P. erminea) common to the old and new worlds. The feet are more or less hairy beneath, especially the hinder part of tarsus. Habit digitigrade. The nose bears a median vertical groove. The Mink (P. vison) is aquatic in its habits. There may be from 13 to 16 dorsal and 5 or 6 lumbar, the dorsal and lumbar vertebrae together varying from 19 to 21. The lumbar region is at its maximum of relative length amongst Arctoids, and the dorsal region almost at its minimum. The limbs are at their minimum length as compared with the spine, as are also the femur, tibia, and metacarpus. The length of the palate, and the breadth of the zygomata, compared with the length of the skull, are also at their minimum. The infraorbital foramen is larger relatively than in Mustela, and the mastoid and paroccipital processes are still more indistinct \ 1 P. Z. S. 1869, p. 39, Martes. 2 L. c. p. 17. 3 This is Mustela of Aldrovandus, Ray, Klein, Schreber, Gmelin, Desmarest, Lesson, Fischer, Bell, Gray, and Coues, see'Fur-bearing Animals,' p. 102. It also includes the Gale, Gymnopus, Lutreola, Neogale, and Vison of Gray. It is the Putorius of Cuvier, Brandt, Gray, Richardson, Audubon and Bachman, Coues, P. Gervais, and others. 4 For other cranial characters see Flower, P. Z. S. 1869, p. 13 & fig. 4. |
