XIII CHARACTERS OF ARCTOIDEA 425 
swollen, and there is but little flattening towards the meatus: 
the paroccipital processes, though slight, are in contact with the 
bullae basally, though their free tips are turned away from them. 
Finally, in /etonyx the bullae are much swollen; there is but little 
flattening towards the meatus, and the paroccipital processes, them- 
selves much swollen, are pressed closely against the bullae. The 
Mustelidae, therefore, in this as in other characters, approach the 
Aeluroids. 
There is no caecum, a feature which marks off the Arctoidea 
from all Carnivora except the Viverrids WVandinia and <Arctictis 
(occasionally). The brain is characterised by the possession of 
Cur 
Fic. 212.—Section of the left auditory bulla and surrounding bones of a Bear (Ursus 
Jerox). am, External auditory meatus ; bO, basioccipital ; Car, carotid canal ; 
e, Eustachian canal ; g, glenoid canal ; Sq, squamosal; 7, tympanic ; ¢, tympanic 
ring. (From Flower, Proc. Zool. Soc. 1869.) 
what Dr. Mivart has described as the “ ursine lozenge,” a tract 
about the middle of the hemispheres, defined posteriorly by the 
crucial sulcus, and formed by the emergence on to the surface of 
the brain of the hippocampal gyrus. 
The Arctoidea are very widely distributed. But there are 
some curious exceptions. Thus there are no representatives of 
the group (as might be expected) in the Australian region; they 
are completely absent from Madagascar; while the true Bears 
(family Ursidae) are totally absent from Ethiopian Africa, and 
are only represented by a single species, Ursus ornatus, in the 
Neotropical region. 
It is noteworthy that the Arctoidea never show spots or 
