510 Proceedings of the Koyal Society of Edinburgh. [Sess. 
in the adults had been mounted as natural skeletons and the bones bad 
retained their normal relations.* The carpal articulations of the radius were 
with the radiale, intermedium, and apparently with the os centrale ; those 
of the ulna were with the intermedium, with carpalia 4 + 5, slightly with 
carpale 3, and also with metacarpal v. 
Anderson stated that the carpal bones in Platanista were subject to 
variations in number, even in the opposite limbs of the same individual. 
Whilst six were generally seen, they might in some animals be reduced to 
three, owing to amalgamation of certain carpal bones with each other or even 
with the ulna. Kukenthal, who subsequently studied the carpus of this 
species in skeletons in the museums in London and Leiden, also recognised 
differences in number, and, whilst agreeing with Anderson’s interpretation of 
some of the bones, differed from him in regard to others.f 
The study of the ten hands now under consideration has confirmed the 
statements made by my predecessors in regard to variations in the number 
of carpal bones and to the occasional want of symmetry in the two limbs. 
The problem to be solved, notwithstanding the variations, is to determine 
which carpal bones are present in the hand of any specimen of Platanista 
under observation, and also to specify those which are absent. 
In attempting to ascertain their morphology I have followed the plan 
pursued in my previous memoir on the Ziphioids and the Delphinidse, and I 
have regarded the manus of Hyperoodon as providing the necessary key.J; 
In Hyperoodon the proximal carpal row, procarpus, consisted of three bones, 
radiale, intermedium and ulnare : the distal row in the most complete 
specimens had five bones, now named carpalia 1 to 5 in their order from 
the pollex to the minimus, each of which was associated with the metacarpal 
of a numerically corresponding digit. An ossified pisiform might also be 
present at the ulnar border, and in some specimens an os centrale also. 
In the skeletons of the adult Platanista the carpal bones, flattened on 
the dorsal and palmar surfaces, were usually polygonal in outline, and the 
margins formed borders of articulation with adjacent bones, the distance 
between them consisting of a narrow interval which represented the inter- 
* The humerus of the adult St Andrews specimen showed an interesting pathological 
condition : the head, with the adjoining part of the shaft, was hollowed into a large cavity, 
and the articular surface, as well as that of the glenoid cavity, was roughened with bony 
nodules ; possibly the animal had been shot early in its life and a bullet had lodged in the 
bone and hollowe 1 out the cavity, from which doubtless pus had freely discharged. 
t “Die Hand der Cetaceen,” Vergleich. anat. Entwick. Untersuch. an Wahltieren , Zweiter 
Theil, 1893, Jena. 
In Eschricht’s specimen six carpal bones apparently were present, but no details were 
given. See Wallich’s translation, Ann. and Mag. Nat. Hist., March 1852. 
| See my memoir on Sowerby’s whale, Journ. Anat. and Phys., vol. xx., Oct. 1885. 
