OF THE CANIDA AND URSIDA. 929 
with Cuon and Lycaon in the Cuon-group opposed to the Canis- 
group containing Canis, Vulpes, and Otocyon*. 
On the contrary, the distinctness of Speothos may, | think, be 
justifiably expressed by setting the genus aside in a special 
subfamily, the Speothoinz, the remaining genera being called 
Canine. 
There is, as yet, no agreement respecting the number of genera 
into which the Canide are divisible, but all recent zoologists are 
in accord in admitting Lycaon, Cuon, Canis, Vulpes, Otocyon and 
probably Vyctereutes and Urocyon. Both Vulpes and Canis have 
been further subdivided into many genera or subgenera. 
Thomas, for instance, has recently shown that, apart from 
Speothos, the following South American dogs have been 
generically named as follows :—Chrysocyon for jubatus; Dasicyon 
for antarcticus ; Cerdocyon for thous (= cancrivorus) and brasi- 
hiensis (= azare); Pseudalopex for magellanicus, azaricus, etc., 
and Lycalopex for vetulus. At present, however, these genera 
are, | believe, merely nominal, in the sense of being undefined. 
There will be time enough to discuss their validity when the 
distinctive features have been ascertained and stated ; and the 
same may be said for such subdivisions of Vulpes as Vennecus and 
Zerda. Possibly extended study of the feet and other external 
features may help the settlement of this difficult question. 
Family Urnsip# . 
The subjoined account of the feet and the noses of the 
Urside is based upon the examination of examples of the 
following species that have died in the Gardens, namely, the Polar 
Bear (Thalarctos maritimus), the American Black Bear (Ursus 
americanus), the Himalayan Bear (Zremarctos thibetanus), and 
the Sloth Bear (Jelursus wrsinus); and secondly, upon observa- 
tions on living examples in the Society’s menagerie and upon 
dried skins in the British Museum, The four species in question 
exhibit the extreme range of variation in the structure of the 
feet, the Polar Bear and the Sloth Bear being at opposite poles 
in the matter of modification; and all the other existing species 
of bears agreeing, apart from minor details, either with 
U. americanus or with 7’. thibetanus. 
The general shape of the feet of bears is well known. 
Measured from the carpus or the tarsus to the tips of the 
phalanges, they are remarkably short and broad. The five digital 
pads form a slightly curved line, the second, third, and fourth 
being nearly on a level and a little in advance of the first and 
fifth. A short distance behind these pads, and separated from 
them by a comparatively thin-skinned depression, comes the wide 
* By Matthew and Osborn (‘The Age of Mammals,’ 1910). I do not, however, 
know the nature of the evidence on which this classification was based. 
+ Ann. Mag. Nat. Hist. (8) vol. xiii. p. 352 (1914). 
+ For the generic terms adopted for this family see infra, pp. 9389-940. 
