The:patella (d) is comparatively small and compressed laterally ; it is sharp in front, and the applied surface exhibits two well marked facets.
The tibia (2) is the longest bone of the hind leg, and is chiefly remarkable for the prominence of its spine, which projects from the upper fourth of the shaft and presents a sharp ridge directed outwards. A long styli formfibula is stated to exist in Moschus, which is united to the external border of the tibia. In the Javanese Musk preserved in the Edin burgh College of Surgeons Museum, there is no appearance of this bone. Slight traces of the fibula, however, are met with in other cervine genera, in the form of small osseous nodules jutting from the head of the tibia, and in some of the Deer tribe there is likewise to be noticed a small bone constituting the external maleolus (fig. 346, D A. 3). This supplementary piece is, in all probability, the representative of the lower end of the fibula, and it is articulated by three distinct facets to the tibia, os calcis, and the astragalus.
The bones of the tarsus, properly so con sidered, are five in number, viz., —os odds, (2) and os astragulus (5), two ossa cunei formes (8), and a single mass (9) resulting from the union of the os acaphoides and os cu boides. In the Giraffe and in certain Antelopes and Deer the two cuneiforms are conjoined. The bone of the heel is in all much elongated.
ln Camelidm the scaphoids and cuboids (ro and 9) are disconnected.
In conformity with the disposition of the metacarpal bones in the anterior limbs, the metatarsals form a single cannon bone pos teriorly (10). More evident traces of ori ginal duplicity are observable in the latter, than in the corresponding cylinder of the fore-limb, owing to the presence of a fur row in front in addition to the one placed behind ; the latter groove being moreover particularly deep. In Cervidm and Ante lopidm, splint-bones homologous with the metatarsals of the second and little toes of the human subject are occasionally present, to support two supernumerary digits as obtains in the fore-leg; but these spurious phalanges are sometimes seen without the styliform appendages. In Moschus the rudi mentary metatarsals acquire a much greater significance, extending upward nearly as far as the tarsus (c, fig. 348.). We have already alluded to a similar peculiarity in the meta carpus of this aberrant genus. The disposi tion of the true digital phalanges and their accompan3ing essa sessamoidea simulates in every respect that displayed in the con struction of the cloven foot of the anterior extremity.
MvoLony.—The muscles of ruminants ex hibit few peculiarities apart from those of quadrupeds generally. They present arrange ments very similar to those seen in Solipeda, and in the article devoted to the considera tion of that group, numerous comparisons have been instituted in reference to the rnore important myological deviations found in this order. Selecting principally the Ox and
Sheep as types, we have to offer, in regard to this great system of motary organs, the following particulars :— Panuiculus carnosus.—Traces of this super ficial muscular investment exist over the whole surface of the trunk, but in certain localities the fibres are more cogent, and form separate bundles, so as to assume more or less the character of distinct muscles. Eight or ten such bundles may be remarked in different species. In the first place we have a broad band extending from the fore-part of the neck, and spreading toward the lips and forehead ; this constitutes the nzusculus cu taneous faciei. Again, it is very strongly marked at the neck, especially in the Sheep ; here it is denominated the m. cutan. colli. In other domestic animals of the non-ruminant kind, such as the Dog, Cat, and Pig, this se cond division of the fleshy envelope is still more striking. Over the shoulder of the Ox there is a third layer of thickened fasiculi (m. cutan. hunter° ; and lastly, we find a highly developed mass, taking its origin from the fascia lata of the thigh immediately above the patella, and proceeding forward, the fibres radiate toward the scapula in front and the abdomen below ; this is the m. cutan. maximus seu abdonzinis. The insertion of the panniculus is directly into the skin, which everywhere covers it, and " on this texture it can alone act, seeing it is completely isolated from the deeper seated parts, by an universal layer of fascia, which thus enables it to slide more freely upon them. When in action, the fibres throw the skin into folds that form right angles to their general course ; the chief points from which they act being the angle of the jaw, the scapula, the patella, and the pubis."* The principal function appears to be that of serving as an instrument of de fence. By its action animals have the power of jerking and shaking the skin, thus removing irritating matters, — also of erecting bristles and spines as instanced by the defensive arrnature of the Hedgehog,—and in aiding the process of lactation, as obtains in the Marsupiatm. Were it not for the constant and involuntary action of the muscle, the torture (to which many animals, particularly cattle, are subjected, from the stings and bites of flies and other insects), would become intolerable, and consequently we find in those creatures which are most exposed to their in,jurious attacks a preponderating de velopment of this structure.