70 Proceedings of Boy al Society of Edinburgh. [sess. 
Radius was 18 J inches long and simple in form. The Ulna was 
nearly 18 inches long, and had a remarkably large hook-shaped 
olecranon process, of which 6 inches at and near the tip consisted 
of unossified cartilage. The carpal end of each of the two hones of 
the forearm was covered by a cartilaginous plate, which was separ- 
ated by an imperfect joint cavity from the cartilage which covered 
the adjoining surface of the proximal row of carpal hones. The 
bones of the forearm had no separate bony epiphyses. 
The Manus was tetradactylous. The Carpus consisted of five 
bones arranged in a proximal and a distal row, with in addition a 
pisiform bone. The five bones of the two rows were flattened on 
their dorsal and palmar surfaces where they were covered by perios- 
teum and ligamentous bands, whilst the other surfaces (except the 
outer surface of the radiale) were encrusted by cartilage, and were 
articular. The original cartilaginous carpus was so well ossified 
that, except in the pisiform element, only narrow bands of cartilage 
separated the hones from each other. Depressions on the surface 
indicated the line of demarcation between the cartilages which 
covered adjoining carpal bones and the carpal ends of the metacarpal 
bones. 
The proximal row, procarpus, consisted of radiale, intermedium, 
and ulnare. Their size may be gathered from the transverse dia- 
meter of their osseous parts : that of the radiale was 2 J inches ; of 
the intermedium the same ; of the ulnare, 2 J inches. The radiale 
articulated, by its proximal surface with the radius ; by its distal 
with the metacarpal segment of digit a; by its ulnar with the 
intermedium and the more radial (Ca) of the two distal carpals ; 
whilst its outer surface was non-articular. The intermedium 
articulated, proximally with both radius and ulna, especially the 
former; distally with the two carpals of the distal row; radially 
with the radiale ; by its ulnar surface with the ulnare. The ulnare 
articulated, proximally with the ulna ; distally with the more ulnar 
(Cy8) of the two distal carpals, and with the metacarpal segment of 
digit d ; radially with the intermedium ; by its ulnar surface with 
the pisiform. The pisiform element, like the olecranon process of 
the ulna, contained a considerable proportion of cartilage, which 
had a recurrent direction close to the border of the ulna ; the pisi- 
form articulated with the cartilage at the lower end of the ulna, 
