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written thus, called Neaouyang or Shantoo.” (Heuen &c., Part 12, Zoology, page 9).
This closes the chain of evidence collected relative to the animals which have any pretensions to rank in their works with mankind. The observations made with regard to the Sing-sing apply very nearly here. The same difference of native opinion casts the same doubt upon the authenticity of their accounts. Natural History, as a science even of observation, has been, and under the present system always will be, at a low condition among a people, where all knowledge but that of government and morals, ranks scarcely above the mechanical arts. The collection of a few popular traditions, --the rough delineation of objects as vaguely seen, not comprehended, -has been all that China can boast; and the practical and deeply-theoretical examinations and inductions which build up the towering structure of western lore, must be infused into them from without, the Chinese have it not in them, and, with their distaste for innovation, they never can examine the products of nature with the eye of accuracy and generalizing power. The Zoology of the San tsae too hwuy is a glaring instance of this; the fabulous and the true - imagination and observation—are alike blended in a disorder startling to a European eye. The 'Urhya' is rather more correct, for it has at least the merit of arrangement in great classes, wide and abrupt in their transitions, but still holding out sufficient landmarks for future improvement. The “Shan hae king' is one mass of confusion; it rejects indignantly all arrangement. The Japanese Encyclopedia has a mere glimmering of presenting its animals according to their type ;-an idea feebly maintained. The only work in which the writer of the present article has seen any allusion to the modern system, was in one apparently new, where the artist had, in addition to some birds, depicted the claws and beaks, which must have been gathered from some European work, since such was utterly beyond Chinese power. Yet we must still concede to the Chinese that they have observed and noted, to the best of their ability, the animals existing in their own country, and have most signally failed where they have relied on mistaken information afforded from external sources; and that European writers of their date present as little truth.
( To be continued.)
Art. V.- Observations on the Rodentia, with a view to point out
the groups as indicated by the structure of the Crania, in this Order of Mammals. By G. R. WATERHOUSE, Esq., Curator to the Zoological Society, Vice-Pres. of the Entomological Society.
(Continued from page 279.)
DENTITION.-Incisors as broad as deep, nearly cylindrical : molars } }, or 44, rootless.
Skull.Ant-orbital opening of moderate size, or small; anterior root of the zygoma thrown up from the plane of the palate: temporal bone produced anteriorly and laterally, and encroaching on the temporal fosse : palate more or less contracted in front, the inter-molar portion descending more or less below the level of the anterior portion.
Lower jaw.—Coronoid process large (usually very large); articular surface of the condyles broad,—in some species with the transverse diameter equal to the longitudinal: descending ramus with the angles twisted outwards, and situated above the plane of the crowns of the molar teeth."
The genera Castor, Ondatra, Arvicola, Lemmus, Geomys and Spalar, belong to this family.
A transverse section of an incisor tooth, in Arricola presents a nearly circular figure (fig. 70,) and in this respect differs from Mus, in which the incisors (m) are almost always compressed and deeper from front to back, and where the sides and front are nearly flat. In the molar teeth in the present family the folds of the enamel generally divide the tooth into angular-shaped portions, as represented in the figure of the skull of Ondatra, and these teeth are rootless, and continue to grow at the base as they wear away at the opposite extremity; but in aged individuals the supply of pulp decreases, and the base of the tooth begins to divide into two or three false fangs, as in fig. 70, k, which represents a molar tooth of very old specimen of the Muskwash. I say false fangs, for these roots are of an irregular form and unlike the true fangs of the rat's molars.
1 The only rodents I am acquainted with, besides the Arvicolida, in which the descending ramus of the jaw is thus raised, are those belonging to the genus Cricetus, but here this process is of the same form as that of the rat, and the space occupied by the molar teeth is remarkably small, whereas in the Arvicolidæ it is great.
The molar teeth of Spalax (n and o) possess the same irregular-formed and imperfect fangs as are found in old specimens of Arvicola and Ondatra, but apparently they have these fangs at an early age, and thus evince approach, as regards the teeth, to the Muride. The cranium in the Arvicolide is usually rather broad, and proportionately shorter than in the Muride; in Ondatra, Arvicola, and Lemmus,
(k) molar tooth of an aged specimen of Ondatra. (1) section of incisor tooth of Arvicola. (m) section of incisor of Mus. (n) and (o) molar teeth of Spalax.
the temporal bone is produced anteriorly and laterally, and in some of the species forms an angle, as in Arvicola am
phibia, and Ondatra (a); in Lemmus Norvegicus and many of the smaller species of Arvicola this portion is rounded; in the remaining three genera, Geomys, Spalax and Castor, the temporal bone is less produced; it nevertheless encroaches considerably on the temporal fosse in these genera. The superior maxillary bone sends backwards a lamellar process (6 in the figures), in most of the species of the present family, as in the Muride; Castor and Geomys, however, afford exceptions. These two genera differ moreover in having a very small ant-orbital opening, which is situated far forward ; in the former there is a projecting fold of bone which protects the anterior outlet of this opening. In most Arvicolide, the malar bone is broad and vertically compressed; it is immensely developed in the beaver, and unlike other species of the present group, runs up to join the lachrymal bone. On the other hand, in the two genera Spalax and Geomys, it is small and very slender.
The anterior root of the zygoma is in the form of a thin plate, of considerable extent. This plate is oblique in its position, and its lower edge is emarginated as in the rats. The genus Spalax forms an exception, this plate being of but small extent.
The incisive foramina are tolerably large in Ondatra, Arvicola and Lemmus, but small in the remaining genera ; they are always situated partly in the inter-maxillary and partly in the maxillary bones, excepting in Geomys and Castor, where they are confined to the inter-maxillaries.
The palate is moderately broad and but slightly contracted between the anterior molars, in Arvicola, Ondatra and Lemmus; in Spalax and Geomys it is narrow, and in the beaver it is much contracted between the anterior pair of molars, but' expands posteriorly. The skull in Geomys (fig. 71) is remarkable for the peculiar form of the posterior portion of the palate. The two pterygoid bones converge and meet in front, where they expand, and joining with the palatine bones form a horizontal platform, which is situated between the hinder pair of molars, and considerably below the plane of the palate; opening on to this platform are two large foramina, which are the outlets of two horizontal canals : these canals run under the palatine bones, and open in front of them, and are then continued forwards on the palatine portion of the superior maxillary bone, in the form of two deep grooves. A similar structure may be seen, but in a less marked degree, in the common water-rat, and some other Arvicolæ.
1 The malar bone of the heaver differs also from other Arvicolide, inasmuch as it enters into the composition of the glenoid cavity.
Skull and lower jaw of Geomys umbrinus ? The same skull (Geomys) possesses two or three other peculiar characters which are worthy of notice, particularly the broadly expanded and almost flat form of the glenoid cavity of the temporal bone, the very small size of the antorbital foramina, which consist merely of two short vertical slits, and the straightness of the nasal bones; these are but very slightly broader at the apex than at the base, and not distinctly expanded in front as in other Arvicole. The interparietal bone is small and nearly of a semicircular form.
Skull and lower jaw of Spalax typhlus. The skull of Spalax typhlus (fig. 72), like that of Geomys, has a broad and very slightly concave glenoid cavity to the