CANIDE 547 
or heel, occupying about one-third of the whole length of the tooth. 
The second molar is less than half the length of the first, with a 
pair of cusps placed side by side anteriorly, and a less distinct 
posterior pair. The third is an extremely small and simple tooth, 
with a subcircular tuberculated crown and single root. 
The cranium (Fig. 249) is more or less elongated, the facial 
portion tapering forwards and compressed. The jaws are elongated, 
and the zygomata moderately strong. The postorbital processes of 
the frontal short, leaving the orbit widely open posteriorly. Verte- 
bre: C 7,D 13, L 7,8 3, C 17-22. Clavicles present, but very 
rudimentary. Limbs of moderate proportions, digitigrade. Feet 
short ; five toes on the fore foot, the pollex much shorter than the 
others, and not reaching to the ground. Four toes on the hind 
foot, the hallux being represented by a rudiment of the metatarsal.! 
All the toes are provided with exserted, non-retractile, slightly 
curved, and blunt claws, which, being exposed, become worn at the 
tips. Tail moderate, or rather long, generally somewhat bushy. 
The pupil of the eye, when contracted, is in some species round, in 
others elliptical and vertical. 
This extensive genus may be considered as truly cosmopolitan. 
One or more species occur in every part of the American continent 
from Greenland to Patagonia and the Falkland Isles; and similarly, 
in the Old World, Europe, Africa, and Asia, with most of the large 
islands adjacent, and even Australia, have their wild Dogs, though 
in the last case they may belong to a feral race, introduced origin- 
ally by man. They are generally sociable animals, hunting their 
prey in packs. Many species burrow in the ground; none habitu- 
ally climb trees. Though mostly carnivorous, feeding chiefly on 
animals they have chased and killed themselves, many, especially 
among the smaller species, eat garbage, carrion, insects, and also 
fruit, berries, and other vegetable substances. The species are 
very numerous, and, as in most other large genera, very ill-defined, 
few zoologists agreeing as to which of the many slightly different 
modifications should be considered as local varieties and which true 
species. Perhaps the best cranial character by which the different 
members of the genus can be distinguished is that pointed out by 
Burmeister, viz. that in the animals generally called Dogs, Wolves, 
and Jackals the postorbital process of the frontal bone is regularly 
smooth and convex above, with its extremity bent downwards, 
whereas in Foxes this process is hollowed above, with its outer 
margin (particularly of the anterior border) somewhat raised. This 
modification coincides in the main with that upon which Professor 
1 In Domestic Dogs a hallux is frequently developed, though often in a rudi- 
mentary condition, the phalanges and claw being suspended loosely in the skin, 
without direct connection with the other bones of the foot ; it is called by dog- 
fanciers the ‘‘ dew claw.” 
