rge penial bone.

Dog tribe.

From all the other members of the group the _Canidae_ are broadly
distinguished (in the case of existing forms) by the large and
well-developed tympanic bulla, with which the paroccipital process is
in contact. An alisphenoid canal is present. The feet are digitigrade,
usually with five (in one instance four) front and always four
hind-toes. The molars--generally 2/3--have tall cusps, and the
sectorials are large and powerful (figs. 1 and 2). The intestine has
both a duodeno-jejunal flexure and a caecum. A prostate gland is
present; but there are no glands in the vasa deferentia; the penial
bone is grooved; and anal glands are generally developed. The
distribution of the family is cosmopolitan. The normal dentition is i.
3/3, c. 1/1, p. 4/4, m. 2/3; total 42; thus differing from the typical
series only by the loss of the last pair of upper molars (present in
certain extinct forms). In the characters of the teeth the group is
the most primitive of all Carnivora. Typically the upper secterial
(fig. 1, II) consists of a stout blade, of which the anterior cusp is
almost obsolete, the middle cusp large, conical and pointed backwards,
and the posterior cusp in the form of a compressed ridge; the inner
lobe is very small, and placed at the fore part of the tooth. The
first molar is more than half the antero-posterior length of the
sectorial, and considerably wider than long; its crown consists of two
prominent conical cusps, of which the anterior is the larger, and a
low, broad inward prolongation, supporting two more or less distinct
cusps and a raised inner border. The second molar resembles the first
in general form, but is considerably smaller. The lower sectorial
(fig. 2, II) is a large tooth, with a strong compressed bilobed blade,
the hinder lobe being considerably the larger and more pointed, a
small but distinct inner tubercle placed at the hinder margin of the
posterior lobe of the blade, and a broad, low, tuberculated 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.

Views differ in regard to the best classification of the _Canidae_,
some wri