MR. W. H. FLOWER ON THE OSTEOLOGY OF THE SPERM-WHALE. 365 
of the Toothed Whales, ¢. g. Globiocephalus, the metacarpals and phalanges are com- 
pleted by very large epiphyses. The cartilaginous plates terminating two contiguous 
bones are not blended together as in the Whalebone-Whales (where the phalanges 
appear only as separate ossifications in a continuous rod of cartilage), but are quite 
distinct, and, when a longitudinal section is made, show a free space between them, not 
unlike a synovial cavity; but the dry condition of the specimens prevented a very satis- 
factory investigation of this point. 
The digits spread considerably from each other, giving breadth to the hand; the fifth 
especially stands far apart from the others; but the first, or thumb, is, as usual, 
adpressed towards the second digit. The first is by far the shortest; the second the 
longest; the third almost equal to it; the fourth slightly, and the fifth considerably 
shorter. The phalanges generally are elongated, compressed, and narrower at the 
middle than at the ends, the last peculiarity being more characteristic of the meta- 
carpals and proximal phalanges than of those situated more distally. 
The exact enumeration of the phalanges of the digits, for any given species of Ceta- 
cean, is never very easy, as the terminal bones are often slow and irregular in their 
ossification, sometimes being represented only by cartilage, or by minute nodules of 
bone readily lost in the process of preparation. 
As none of the hands belonging to the skeletons examined were quite perfect, I 
have given a figure of this part from another specimen, in which all the bones are 
retained in their exact relative position and distance apart (Plate LXI. fig. 1). The 
pisiform bone and the terminal phalanx of the second finger were wanting in this other- 
wise complete specimen; they have been added to the figure from another of the sepa- 
rate pectoral limbs sent to the Museum by Mr. Crowther. 
The first digit has a short metacarpal, the broad upper extremity of which articulates 
above with the scapho-trapezium, and by its side with the second metacarpal. This is 
succeeded (in the specimen figured) by a single slender tapering phalanx, the apex of 
which reaches rather below the articulation between the metacarpal and first phalanx 
of the second digit. Although in the present specimen this is a single bone, it appears 
usually to consist of two, the terminal one being much the smaller, and generally more 
or less ankylosed to the other. In some cases I have found them completely distinct. 
In one of the hands belonging to the Tasmanian skeleton, these phalanges are not only 
united together, but also to the distal half of the contiguous second metacarpal (see 
Plate LY.). 
The second digit has a large metacarpal, which may be distinguished from all the 
others, by its superior size, and by a small lateral articular surface on the radial side of 
its proximal extremity, where it is in relation with the first metacarpal. his bone is 
followed by five phalanges gradually diminishing in size. 
The third digit has likewise five phalanges, besides the metacarpal; and the fourth 
has four. The metacarpal of the fifth digit differs from the others in being narrower in 
