﻿CANIS. 13 



thought best when describing the teeth not to use terms involving assumptions of 

 homology and requiring long explanatory prefixes. The terms " cusp " and 

 "tubercle " are regarded as synonyms for small elevations of the surface of a tooth. 

 The term " cone " is used as denoting a rather larger elevation, and the terms 

 "talon" or "heel " for posteriorly-placed segments of a tooth. 



(2) Permanent Dentition of the Upper Jaw in Cams lupus (PI. V). — In drawing 

 up the following description, the skulls and teeth of a number of wolves, recent and 

 fossil, now preserved in the British Museum have been examined, but the principal 

 part of the description is based on a skull of a male wolf from Pekin, No. 90.7.8.2 

 in the British Museum collection. 



I. 1 and 2 are very similar teeth, differing only in the slightly larger size of i. 2. 

 The principal cone is somewhat recurved and there are small laterally-placed 

 accessory cusps. The cingulum is rather strongly marked. In some cases the 

 lateral accessory cusps are scarcely noticeable, but the cingulum is raised into 

 slight cusps posteriorly. The root is about three times as long as the crown and 

 is much laterally compressed. 



I. 3 is a rather larger and more caniniform tooth than i. 1 and 2 and shows 

 some variability, the postero-internal face being sometimes marked by a cingulum, 

 sometimes raised into a pair of laterally-placed cusps. The root is about twice 

 as long as the crown and is triangular in cross-section, not laterally compressed as 

 in i. 1 and 2. 



C. The canine has the form usual in the Carnivora. Its crown constitutes 

 about two thirds of its length. 



Pm. 1 is a small, single-rooted tooth with a fairly well-marked cingulum 

 surrounding the principal cone. Very slight accessory cusps may be developed 

 on the cingulum posteriorly and antero-internally. 



Pm. 2 is a larger and more elongated two-rooted tooth with a conical crown 

 triangular in outline. A posteriorly-placed cusp may be present or absent. 



Pm. 3 closely resembles pm. 2, differing only in its larger size and in the 

 greater prominence of the posterior cusp, which may be double. 



Pm. 4 , the upper carnassial, is a large three-rooted tooth with a powerful 

 trenchant blade divided into an anterior more conical portion and a posterior 

 portion with a chisel-like edge. Placed anteriorly is a low inner tubercle supported 

 by a distinct root. 



M. 1. This is a large tooth, somewhat wider than long. The outer portion of 

 the crown is formed by two prominent cones of which the anterior is the larger ; 

 the inner portion of the tooth is much depressed, but the inner edge is raised into 

 a more or less prominent ridge and two low cusps lie between this and the 

 outer portion of the tooth. Two roots support the outer portion, and a third and 

 stouter root the inner portion. 



