THE MARSUPIAL ANT-EATERS., 183 
think, it should not be referred to a family by itself. Regarding 
it as the representative of a sub-family only, the AZyrmecodiine 
will be distinguished from the preceding sub-family of the 
Dasyuride by the following characteristics :— 
Tongue long, cylindrical, and extensile; nose naked, and 
grooved below ; lower lip pointed, and projecting beyond the 
teeth ; chest furnished with a complex gland, opening to the 
surface by means of several large and distinct apertures. Cheek- 
teeth small and delicate, the molars being more than four in 
number on each side of both the upper and lower jaw, and 
those of the latter with their inner cusps larger than the outer 
ones. 
As a genus, AZyrmecobius may de defined as follows :— 
Form graceful and Squirrel-like ; ears long and narrow; fore 
feet with five, and the hinder with four toes, the hallux being 
wanting externally ; all the toes furnished with long claws 
adapted for digging ; soles of fore feet partially, and those of 
hind pair entirely, naked, their pads small and granulated. 
Tail long and bushy. Pouch obsolete. ‘Teats, according to 
Thomas, four in number, although there is a statement of 
. Gould implying the existence of seven or eight. Three pairs 
of premolar teeth in each jaw, and five pairs of molars, with 
the occasional presence of a sixth pair in the lower jaw; the 
total number of teeth, inclusive of the incisors and canines, 
_ thus being either 50 or 52. Very rarely a fourth pair of lower 
incisors occurs, bringing up the extreme total to 54. 
The especial interest of this genus, in which the number of 
teeth is greater than in any other mammals which have the teeth 
| differentiated into series, lies in its relationship to the extinct 
_ Marsupials of the Mesozoic rocks of Europe, as exemplified by 
_ the form and number of its molar teeth. Since these teeth are 
very remarkable, and unlike those of any other living members 
_ of the order, they merit especial notice. In the words of Water- 
