DR. J. MURIE ON THE ANATOMY OF THE SEA-LION. 515 
wide hollow; the inner glides upon the radius ; a narrow corner of the anterior impinges 
against the scapholunar, its remainder articulating with the unciform ; and an outer facet 
partly accommodates the fifth metacarpal as the manus is twisted outwards. The 
pisiform is a small bean-shaped bone, its free end directed outwards, its attached end 
lying upon the epiphysis of the ulna and the cuneiform of the four articular surfaces 
presented by the trapezium ; that towards the second metacarpal is a mere corner facet. 
The trapezoidal is smaller than the trapezium, its palmar surface being very consider- 
ably narrowed. It just touches the third metacarpal, besides its ordinary facets for 
scaphoid, magnum, trapezium, and first metacarpal. The os magnum is the least-sized 
bone of the distal row, and, reversely from the last, has a narrow dorsal and broader 
palmar surface. It appears not to come into contact with the second metacarpal, and 
sinks in obliquely and below the scapholunar. Thus when the manus is planted on the 
ground the latter bone overrides it in great part. The unciform is about equal to the 
trapezoides in magnitude. It is surrounded by five bones, the fifth metacarpal more 
usually constituting its outer boundary. 
The metacarpals are of most unequal dimensions, that of the pollex being of inordi- 
nate proportions. The lengths from lst to 5th are as follows :—4:25, 3, 2°3, 2, and 
1:9 inch. The first is by far the broadest, thickest, and flattest; the third thinnest and 
roundest. The fifth differs from the fourth in being awider bone. The proximal ends 
of the outer four are enlarged and tuberose; the width of the innermost (first) subdues 
its otherwise bulky character. 
The phalanges, of normal number, bear a relation to the size of the metacarpals; that 
is, the innermost is largest and longest, the fifth digit a trifle stronger though shorter 
than the fourth. The proximal phalanx of the thumb is powerful, its distal one a short 
flat figure of eight; respectively they are 3-9 and 1°5 inch long. The lengths of the 
remainder of the series are:—second digit 2°7, 2:2, 1; third digit 1:9, 1:6, 1; fourth 
digit 1:5, 0-8, 0.3; fifth digit 1:3, 0°3, 0-2 inch. The spatulate cartilages and that 
extraordinary one of the pollex, which form the digital extremities, I drew attention to 
and figured in my former anatomical contribution. 
b. Pelvic Limb.—Pelvis. The long axis of the entire pelvis is almost identical with 
that of the spinal column, and even in the strange attitude of walking it accords with 
the lumbo-caudal region’. Ilio-pubic and ilio-ischial angles cannot be said to obtain. 
Each innominate bone approaches posteriorly so as to produce a long narrow V-shaped 
pelvis, and with such variation in the thickness of the bones that the brim is lozenge- 
shaped. The ischium and pubis are narrow bars uniting in a thin rounded plate the 
tuberosity, and enclosing a lengthened oval obturator foramen. Their acetabular ends 
thicken; the acetabulum itself is large but not deep. The ilium is a broader strip of 
bone, slightly outturned anteriorly, its sacral border inturned, and with moderate sacro- 
1 Cuvier (J. c. p. 226) briefly distinguishes between the pelvis of the Earless and Eared Seals, a point which 
Allen in his paper (J. c. p. 27) with justice lays great stress on as characteristic of the two groups. 
