516 DR. J. MURIE ON THE ANATOMY OF THE SEA-LION. 
iliac synchondrosis. _Measurements:—Extreme pelvic length 7:3 inches, ilium 3:1, 
pubis 4-2, as is also ischium to mid-acetabulum; the latter 1:3 long, anterior iliac 
angles 3:3 apart, mid iliac breadth or depth 1-2, line cutting acetabulum 1:7, mid 
ischio-pubal 1:3. Diameters of brim—conjugate 4:7, transverse 1:5, oblique 3:3. 
Diameters of outlet—antero-posterior 1:4, transverse 0-4. 
Femur and Patella. The former, at its upper end, has head and trochanteric 
eminence on a level simulating one another—and neither prominent, from the antero- 
posterior flattening and breadth of the short shaft. The intercondyloid fossa is shallow, 
the innermost knuckle largest, and both rather square in figure from being truncate 
below. Femur is 4 inches long. Patella small, rounded, and with a flat articular 
surface. 
Tibia and Fibula. The straight rodlike fibula usually stands quite behind the tibia ; 
its narrowed shaft is sharply triangular. Head badly defined, smaller end more 
expanded. The tibia has a forward bend, a somewhat laterally compressed stoutish 
shaft, and subequally enlarged extremities. The articular end opposed to the femur is 
smooth and pretty equal-surfaced ; but it shelves downwards, backwards, and outwards. 
This posterior inclination is most serviceable, and, indeed, enables the femur to be bent 
on the lower limb at a very acute angle without depriving the muscles of their power 
of action in walking. Moreover, along with unusual freedom of the femur, it 
contributes to the limb being thrown back and up in a line with the tail as in the act 
of swimming. There is a short inner malleolus; and the adjoining astragaloid face has 
double facets. Extreme length of tibia 8-2, of fibula 6-5 inches. 
Hind Foot. When the animal is on all fours the tarsal bones, of the normal number, 
offer perhaps less striking and fewer, but as singular points worthy of notice as the 
carpus. The entire sole (and not a segment of it) is laid on the ground plantigrade- 
fashion in walking. Both astragalus and calcaneum are low. Cuvier’s words (J. ¢. 
p- 226), so applicable to Otaria jubata, will bear quotation. He says:—* L’astragale 
des phoques est trés-extraordinaire, en ce qu’au lieu d’une poulie plus ou moins creuse 
dans son milieu il offre 4 la jambe une poulie convexe formée de deux faces, qui font 
ensemble un angle saillant comme un toit, et dont l'une répond au tibia, et l’autre, qui 
est plus grande, au péroné. Cet os n’a pas seulement une apophyse en avant pour le 
scaphoide, mais il en a une autre en arriére terminée par une tubérosité et formant une 
sorte de talon interne, de maniére qu’en voyant l’astragale isolé on croiroit que c’est le 
calcaneum.” I may note more particularly of the present specimen that the horizon- 
tally ovoid fibular facet looks backwards and inwards, and there is a certain amount of 
the same obliquity apparent in its tibial concavo-convex facet. These dispositions 
concurrently adapt themselves to the peculiarities of tibia and fibula. The plantar 
surface of the os calcis is roughened and moderately convex ; the short calcaneal process 
seems to have an inward tilt. It is not altogether, as Cuvier observes, that the 
calcaneum is placed outside the astragalus, but rather that the two bones have a 
