719 
1908-9.] The Skeleton of a Sowerby’s Whale. 
independence. The disappearance may perhaps in some cases be due to 
atrophy of the cartilaginous centrale, or, as in Mesoplodon and Monodon, 
to its fusion with an adjoining carpal bone. 
The pisiform element of the carpus seems to be constant in the cartila- 
ginous stage, but in my specimens it was undergoing ossification only in 
Hyperoodon and the St Andrews Mesoplodon. 
From the observations of Leboucq and Kiikenthal on the development 
of the phalanges, their number in the adult is less than in that of the 
embryo of the same species, apparently by fusion with each other of 
pieces originally distinct, a condition which applies also to diminution 
in the number of pieces originally present in the carpus. 
In this memoir I have purposely restricted myself to the consideration 
of the carpus in those Odontoceti that I have personally examined. The 
principles which have guided me in ascertaining the morphology of the 
bones can be applied to their determination in other species of whales ; but 
as this paper has reached a length more than I had originally intended, I 
must leave for another occasion their further application. 
As supplementary to my description and figures of the carpus of 
Mesoplodon I append a radiogram of the manus of that animal, which shows 
Fig. 11. — Radiogram of hand of Mesoplodon bidens from Morrison’s Haven. 
distinctly, in the undissected carpus, carpale 1 as a separate bone associated 
with the pollex ; carpale 2 fused with C 3 , as indicated by the notch opposite 
the interval between M n and M m ; carpale 4 fused with C 5 for M IV and M v . 
