1908-9.] 
715 
The Skeleton of a Sowerbv’s Whale. 
M IV with C IV and the cartilage of the possible C v ; M v slightly with that 
cartilage, but mostly with the ulnare. 
The two less advanced specimens had in the distal row the bony carpalia 
which I have designated C 2 + 3 and C 4 ; no ossific nodule was seen in the 
radiograms in the cartilage between the radiale and M I? or in that between 
the ulnare and M v . In both a process of bone projected from the disto- 
radial border of the intermedium, like that which I have interpreted in the 
adult as an os centrale. 
The formula of Monodon monoceros is as follows : — 
Min. 
Ann. 
Med. 
Ind. 
Pollex. 
Ph, 
ff 
Ph 3 
j 
PP 4 
PIP 
Ph 2 
M 
y 
Miv 
Mm 
Mu 
i 
Mi 
c 5 
? o 4 
c, 
I 
+2 
k 
i 
Cen. 
I 
ulnare 
intermedium 
i 
’adiale 
/ 
\ 
/ 
/ 
Ulna 
Radius 
Morphological Summary. 
It will have been seen from the foregoing description that in the 
Ziphioid whales, Hyperoodon and Mesoplodon, and in the Helphinidse, 
whilst the three bones of the proximal row of the carpus, and the pisiform 
cartilage either unossihed or only partially so, are constant in number and 
correspond generally in their arrangement, yet that the distal carpalia 
vary in number, and in their articulations with the procarpus and with 
the metacarpal bones ; also that the ossa centralia are inconstant. 
Hyperoodon should, as I stated in 1885, be regarded as the type in which 
each of the five digits has its corresponding distal carpal, for articulation 
with the metacarpal of the digit to which it belongs. In other genera 
and species, however, a smaller number of distal carpalia are present, and 
the question naturally arises which members of the type-number have 
remained and which have disappeared as independent units. The range 
in number varies from five in Hyperoodon to four, or three, or even two 
in other, species. In my memoir on the Shetland Mesoplodon, 1885, I 
discussed the question of the diminution in the type-number from five 
distal carpalia, and stated that it “ may be due either to one or more centres 
of ossification not having formed in the carpal cartilage, or to the fusion 
with each other of ossific nuclei which were distinct in the younger con- 
dition of the same carpus.” The terminology of the carpal bones introduced 
