26 MR. W. H. FLOWER ON THE [Jan. 14, 
the large size of the os penis, they resemble the former, though the 
os is of a different form, being straight, wide, depressed, and grooved. 
In the distinctness of the prostate gland they approach the Ailuroids. 
The bulbous dilatation of the penis during erection is a special Cynoid 
peculiarity. 
The above-described cranial characters are very constant in all the 
known forms of dogs, even the most aberrant*. The principal modi- 
fications are in the size of the meatus and amount of inflation of the 
bulla, which appear to be in direct relation to the development of 
the external ear, as they reach their maximum in the Fennec. The 
only deviation presenting any approximation to any other family 
that I have observed is in Lycaon, in which the condyloid foramen is 
partly concealed by the ridge from the paroccipital as in the Mlu- 
roids and the Hyzena, an animal with which it bas been supposed 
to have some affinity. But for this slight peculiarity, it presents 
no other deviation from the true Cynoid type. 
Such being the three principal types of Carnivora as indicated by 
the modifications of the base of the cranium, I will next consider 
the position of certain genera about the affinities of which there has 
been some real or supposed difficulty. 
First the Hyzenas, which are placed by Mr. Turner without 
hesitation in his family Felide, equivalent, it must be remembered, 
to the group here called Aluroidea, as they present, he says, “‘ the 
same cranial characters as the cats.” But he appears not to have 
noticed the peculiar septum, which forms such a marked character 
in the Feline or Viverride, and which is completely wanting in the 
Hycenast. 
The cranial characters of this genus (fig. 13, p. 27) are as follows : 
—Auditory bulla inflated, smooth, oval, most prominent posteriorly, 
and rather pointed in front, slightly compressed laterally. Bony 
meatus short, but its anterior lip slightly produced. Bulla perfectly 
simple within, without trace of division into compartments. Carotid 
foramen (car) distinct, near the middle of the inner side of the bulla. 
Paroccipital process (p) spread out over the posterior surface of the 
bulla, and forming a nodular protuberance beyond it, as in the larger 
Felide. Mastoid process (m) slightly developed. Condyloid foramen 
(c) quite concealed by the ridge from the paroccipital to the condyle. 
Glenoid foramen very minute or absent. No alisphenoid canal. 
These characters all agree with the Aluroid type, with the ex- 
ception of the absence of septum to the bulla, and when taken toge- 
ther are perhaps rather more feline than viverrine. ‘The other parts 
of the system which have previously been made use of in the former 
* IT should mention that I have not had an opportunity of examining the skull 
of Icticyon vendaticus; but Burmeister’s figure shows its true cynoid character. 
t Mr. Turner says of the Viverride, ‘The auditory bulla has very distinctly 
the appearance of being divided into two portions, of which the posterior is much 
the larger, and elongated in form: the more anterior division, which encloses the 
meatus auditorius externus, is much smaller, and partly overlapped by the other.” 
—Eoe. cit.p.78. This only refers to the external appearance of the bulla, and is 
given as diagnostic of the bulla of the Viverride as opposed to that of the Felide. 
