514 
Proceedings of the Royal Society of Edinburgh. [Sess. 
also a bone which projected from the ulnar border of the carpus, possibly a 
pisiform. He figured at the radial border two distinct bones separated by 
intermediate cartilage which were probably radiale (scaphoid) and carpale 1 
(trapezium) ; the lunare was undoubtedly the intermedium : it is difficult 
to say whether his cuneiform was ulnare or carpalia 4 + 5 ; for though it 
articulated with the ulna its distal border was almost equally divided 
between metacarpals iv and v ; most likely therefore it was the conjoined car- 
palia 4 + 5 (unciform) and corresponded with the arrangement in Platanista ; 
if this be the correct interpretation, the ulnare (cuneiform) was absent. 
Flower’s magno-trapezoid was, I believe, carpale 3, for it was associated with 
M iii, whilst a bone, which he has numbered 5, was without doubt carpale 2, 
for it obviously belonged to M ii. According to this interpretation the carpus 
of Inia consisted of radiale and intermedium in the proximal row, the ulnare 
being absent : of carpalia 1, 2, 3 as separate bones and carpalia 4 + 5 conjoined 
in the distal row. It would correspond up to this point with the arrangement 
in Platanista, Scheme 1, but differed otherwise in having a pisiform and in 
not having an os centrale. 
EXPLANATION OF FIGURES. 
Fig. 1, scheme 1. Radiogram of right flipper of young Platanista gangetica, 
Dr Amiandale’s specimen, showing radiale-carpale bone. Reduced about Jrd. 
Fig. 2, scheme 2. Radiogram of left flipper of the same animal ; the radiale and 
carpale 1 are distinct bones. Reduced about Jrd. 
Fig. 3. Radiogram of the flipper of the young specimen in Professor MTntosh’s 
collection in St Andrews. Natural size. 
Fig. 4, scheme 3. Drawing of the carpus of an adult in the Anatomical Museum 
of the University of Edinburgh ; fusion of radiale with carpale 1 and of conjoined 
carpalia 4 + 5 with ulna. Reduced. 
Fig. 5, scheme 4. Drawing of the carpus of an adult in Professor MTntosh’s 
collection ; fusion of radiale with carpale 1 and with os centrale. Reduced. 
The radiograms were taken by Mr Ernest J. Henderson, Assistant in the 
Anatomical Museum, and the drawings were from nature by Mr J. T. Murray. 
H. humerus ; R. radius ; U. ulna ; r. radiale ; in. intermedium ; cen. os centrale ; 
Cl, C 2, C 3 carpalia 1, 2, 3; C 4 + 5 carpalia 4 + 5 coalesced; P. pollex; M i, 
ii, iii, iv, v, the corresponding metacarpals. 
(Issued separately August 1 , 1910 .) 
