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Show 1869.] CLASSIFICATION OF THE CARNIVORA. 5 Too exclusive attention has been paid to the characters of the teeth in defining the family divisions of the order. The difficulty in the taxonomic use of these organs arises from the fact that the teeth of all the members of such a limited and well-defined group as the terrestrial or fissipedal Carnivora are formed on the same general type, but with infinite modifications of this type. And as these modifications are mainly adaptive and not essentially indicative of affinity, they reappear in various degrees and combinations in many of the great natural divisions of the order. Thus, as will be shown further on, teeth alone afford us no satisfactory means of diagnosis between the very distinct groups of the Procyonidce and the Viverridce. The teeth of Proteles, though demonstrating undeniably its right to a place in the order, are so rudimentary or generalized that they afford no help whatever to determine its special position. Again the teeth of Gulo are so similar to those oi Hycena, that if this character alone were used, these two otherwise widely differentiated forms would be placed in the closest proximity. Enhydris, among the Mustelida?, and Cynogale, among the Viverridae, might also be cited as examples of strangely modified dentition, with comparatively little corresponding change in other parts. Rather more than twenty years ago the late Mr. H. N . Turner*, in a paper read before this Society, pointed out the importance of certain structural peculiarities of the base of the cranium in the classification of the Mammalia, and especially demonstrated the constancy of these characters in the various members of the natural divisions of the order Carnivoraf. Very few subsequent zoological writers, however, have followed out the indications suggested in that communication ; and Mr. Turner's views as to the position of certain disputed forms, and the general relationship of the groups one to another, have not by any means met with universal acceptance. It seems desirable therefore to test whether the characters chiefly relied upon by Mr. Turner really have the value which he attributed to them. In endeavouring to do this I shall find it necessary to give a more detailed description than the limits of his paper allowed, to supply a larger number of illustrative examples, and, while fully recognizing the great merit of his observations, may find myself occasionally obliged to differ from the conclusions which he deduced from them. It may be objected at the outset that such an investigation cannot be worth the pains bestowed upon it, as any classification founded solely or even mainly on one limited portion of the organization must necessarily be an artificial one. But if it can be proved that the modifications of any one part are always correlated with important variations in several other and quite unconnected portions of the organization, it is obvious that its study will become of great practical * This original and accurate observer fell a victim to his zeal for his favourite science, having died in 1851 from the effects of a dissection-wound. + " Observations relating to some of the Foramina in the Base of the Skull in Mammalia, and on the Classification of the Order Carnivora," by H. N. Turner, jun. (P. Z. S. 1848, p. 63). |
