2 
la téte inférieure, tous les carnassiers se distinguént de /homme 
par sa figure plus étroite du céte externe que le l’interne, et par sa 
division en deux fosses oblique, au moyen d’une aréte arrondie 
qui repond 4 la partie de l’astragale. . . Le phoque l’a cepen- 
dant d’une forme trés-particuliére par l’excessif aplatissement de 
sa moitié supérieure, et par sa facette particulaire inférieure, qui 
est en concavité simple et peu profounde.” 
The astragalar articular face of the tibia in the genera above 
named is not divided into the two oblique fosse by “a rounded 
crest which is applied to the groove of the superior pully-shaped 
face of the astragalus.” It is uninterrupted and more or less ob- 
lique in the transverse direction; always so at the posterior bor- 
der. The inner malleolar process is produced downwards, and 
rests in a concavity on the inner side of the neck of the astragalus. 
The astragalus, which I have seen in several of the species, pre- 
sents a corresponding trochlear face. That is, instead of a groove, 
it presents an open angle upwards, which separates the superior 
from the oblique internal face. The superior plane is flat, but is 
interrupted on the posterior side by a groove. This groove is the 
posterior extremity of that which divides the superior face of the 
astragalus in the higher Mammalia, but here it contracts to a 
point and disappears next the fibular face just as it reaches the 
superior surface. The fibular face is vertical, and shares on its 
posterior part a large ligamentous fossa with the opposed part of 
the fibula. The distal end of the fibula is remarkably stout. - 
This structure finds its counterpart in the internal half of the 
astragalus of the opossum. The arrangement permits a rotary 
movement of the astragalus and thus of the whole foot, on the 
tibia, the fibula with its fixed articulation with the astragalus, 
rotating on the tibia, as in the pedimanous Marsupialia. The flat- 
ness of the inner malleolus in some of the species indicates that 
the capacity for rotation was less in them than in others. This 
arrangement exactly reverses the extensive oblique fibulo-astraga- 
lar articulation seen in the opossum, the Petaurista, Dasyurus, ete. 
Prof. Owen, in describing the astralagus of the wombat (Phasco- 
lomys), says: ‘*The upper articular surface for the tibia is as usual 
concavo-convex, the internal surface for the inner malleolus flat- 
tened, and at right angles with the preceding, but the outer articu- 
lar surface presents a triangular flattened form, and instead of 
being bent down parallel with the inner articular surface slopes 
away at a very open angle from the upper surface, receiving the 
articular surface of the fibula so as to sustain its vertical pressure. 
* * * This form of astragalus is also characteristic of the 
Koala, Petaurists, Dasyures, and the Pedimanous Marsupialia.” 
In one species where the cuboid bones are preserved, it is evi- 
dent that the distal end of the astragalus articulated with this as 
well as with the navicular bone, although the facet of the astraga- 
lus is single and continuous. As the extensive transverse distal 
astragalar face is characteristic of all the species where it is pre- 
served, the contact of the cuboid and astragalus is probably com- 
mon to all of this division. . / 
The dentition of this group is consistent with its reference to 
