. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. 56o MANUAL OF ZOOLOGY. place being taken by a callous pad of hardened gum, against which the lower incisors impinge (fig. 218). There are also no upper canine teeth, and the only teeth in the upper jaw are six molars on each side'. In the front of the lower jaw is a continuous and uninterrupted series of eight teeth, of which the central six are incisors, and the two outer ones are re- garded by Owen as being canines. Upon this view, canine teeth are present in the lower jaw of t
. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. 56o MANUAL OF ZOOLOGY. place being taken by a callous pad of hardened gum, against which the lower incisors impinge (fig. 218). There are also no upper canine teeth, and the only teeth in the upper jaw are six molars on each side'. In the front of the lower jaw is a continuous and uninterrupted series of eight teeth, of which the central six are incisors, and the two outer ones are re- garded by Owen as being canines. Upon this view, canine teeth are present in the lower jaw of the typical Ruminants, and they are only remarkable for being placed in the same series as the incisors, which they altogether resemble in shape, size, and direction. Behind this continuous series of eight. Fig. 218.—Skull of a hornless Sheep (after Owen). / Incisors; c Canines; .- m. Molars and Fr^emolars. teeth in the lower jaw, there is a vacant space, which is fol- lowed behind by six molars on each side. The prsemolars and molars have their grinding-surfaces marked with two double crescents, the convexities of which are turned inwards in the upper, and outwards in the lower teeth. The dental formula, then, for'a typical Ruminant animal, is— 3—3' 0—0 ^ 3—3 c -^—^ ; pm 3—3 3-3. -^=32. The departures from this typical formula occur in the Camelida and in some of the Deer. Most of the Deer conform in their dentition to the above formula, but a few forms (, the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Nicholson, Henry Alleyne, 1844-1899. New York : D. Appleton
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