32. _The wolf's teeth or eye teeth aid us in judging of the age_; though we are bound to state of these that they can be received only as presumptive evidence. The wolf's teeth have not been before alluded to, because they are not concerned in mastication, and are no more than the representatives of those organs which form the continuous chain in the mouths of some other animals. These teeth appear to be of no use to the horse. They are little nodules of tooth-like structure, having minute fangs, which are inserted immediately anterior to the first molars of the upper, being rarely seen in the lower jaw, and when present there, always being even yet more diminutive. These wolf's teeth are generally shed with the first temporary molars, and therefore if they can be seen, it may be assumed that the permanent molars have not begun to appear. The assumption, however, must not be converted into an assertion; for in some instances the wolf's teeth are retained, and, in a few heads, will remain after the horse has reached an age far beyond that of colthood: their presence, therefore, rather leads our expectations than confirms our judgment. 33. _The mode in which the horse cuts his teeth_ remains to be pointed out. It is generally said, that the tooth, originally growing in its circumscribed cavity, pushes its way through the parts which oppose its entrance into the mouth. So mechanical an idea is characterized by a small amount of physiological knowledge, and it is time the notions which attributed development to mere force were discarded. The tooth is first a pulpy mass, very soft and highly vascular; the superior part, or that part which primarily shows itself above the gum, is the first to become consolidated. Enamel and ivory are there simultaneously deposited, and gradually these extend towards the fang. When a portion of the fang is completed, and the time has arrived for the tooth to be cut, those structures which oppose the egress of the tooth are absorbed; the absorption taking place, not only on the internal surface, against which the young tooth has been supposed to exert its force, but also upon the external parts, upon which it could have no effect. By absorption the barrier is removed and the tooth then comes forward. The process is very beautiful, and no less worthy of admiration is the manner in which the milk teeth are shed. The incisors lose their fangs, and just when the permanent teeth appear, the crown of the temporary ones is removed from the mouth. The removal of the fangs of the milk incisors is the result also of absorption, and the same process effects the removal of the temporary molars, only its operation is not precisely similar; for in these last, not only the fang but the greater portion of the crown is taken away, and little more than the table is cast off when the remnant of what once was a tooth is at length shed. The process of cutting the molar teeth will be more clearly comprehended by referring