700 Proceedings of the Royal Society of Edinburgh. [Sess. 
ment in the mammalian carpus, in which the 4th and 5th metacarpals had 
together only one distal carpal, the os hamatum (unciform), a condition 
which he regarded as characteristic of the mammalia. My recognition of 
five distinct distal carpalia in Hyperoodon furnished, however, an example 
in a mammal of conformity in this respect with the earlier reptilian type. 
In a valuable memoir, “ Die Hand der Cetaceen,” * the first part of which 
appeared in 1889, W. Ktikenthal described the hand of a young Hyperoodon 
in which five distinct distal carpalia, “ corresponding,” he said, “ with the 
carpus described by Turner,” were present. They were approximately of 
equal size ; one was associated with the radiale, one with the ulnare, and three 
with the intermedium ; each carpale carried the metacarpal of a digit. Only 
the intermedium, radiale and carpale l possessed ossific nuclei. In an older 
animal five distal carpalia were seen, each with an osseous nucleus. In it 
an os centrale was also present. In the second part of the memoir, 1893, 
Ktikenthal described a section of the hand of Hyperoodon in the Museum 
of the Royal College of Surgeons, London, in the carpus of which were three 
proximal carpals, five distal carpalia, and an os centrale. He had also two 
foetuses of this animal 55 and 15’8 cm. long respectively, in both of which 
carpale 5 was distinct from carpale 4 ; in the larger foetus carpale 2 was 
partially fused with carpale 3 and an os centrale was present. 
The hands in the two specimens which I have personally examined and 
the carpal regions in the five animals described by Ktikenthal prove conclu- 
sively that Hyperoodon possessed five distal carpalia in a large proportion of 
individuals. At the same time it should be stated that a smaller number of 
distal carpalia has been described in some skeletons. Thus Vrolik’s example 
had four bones ; Van Bambeke spoke of four bones, C i and C 2 separate, 
C 3 + 4 conjoined ; Max Weber stated that in one specimen in Amsterdam four 
distal carpals were found, viz. Cj to C 4 , C 5 not being represented ; j* whilst 
in a smaller animal only three bony distal carpalia had been developed, 
the fourth probably not having reached the stage of ossification. 
Delphinidce. 
Delphinus delphis — The Common Dolphin. 
I have dissected two females of this dolphin ; one, 5 feet 5 J inches in a 
straight line, was shot in the Firth of Forth in February 1887 ;J the. other, 
* Vergleich. Anat. Entwicklungsgeschichte untersuch. an JVahltieren, Jena, Erster Tlieil 
1889, Zweiter Theil 1893 ; also in Denksch. der medic. -natur. wiss. Gesellsch. zu Jena , Dritter 
Band, 1889 and 1893. 
t Morphologisches Jahrbuch , May 1888, Bd. xiii., Taf. xxvii. fig. 4, p. 626. 
I Proc. Roy. Phys. Soc. Edin., 1887, p. 346. 
