192 ELEMENTS OF ORNITHOLOGY, 
ulna is placed on the external or posterior aspect of the fore- 
arm, and often shows tubercles which correspond with the points 
of attachment of the secondary ‘“ remiges.” It is somewhat 
longer than the radius, and its proximal end bears posteriorly a 
more or less enlarged prominence termed the olecranon.. The 
two bones articulate at their distal ends with that part of the 
skeleton of the pinion which corresponds with our wrist. In 
the Penguin the bones of the fore-arm are considerably flat- 
tened. 
The skeleton of the pinion consists of three parts :--(1) the 
part called “ carpus,” which corresponds with our wrist-bones ; 
(2) the part called “metacarpus,” which corresponds with the 
bones in the middle, or fleshy, part of our hand; and (3) the 
“ phalanges,” or bones which correspond with those of our 
thumb and fingers. 
The carpus in adult birds never consists of more than two 
bones, which are small, short, more or less rounded or polygonal 
ossicles. In the very young bird there may be one or two other 
small bones which with growth anchylose with the bones of the 
middle hand, 7. e. with the “ metacarpus.” Of the two perma- 
nently distinct carpal bones one lies at the distal end of the 
radius, on which account it is often called the radiale, while it is 
also named the scapholunar bone. The other carpal bone lies at 
the distal end of the ulna, and is called the ware or cuneiform 
bone. The carpal bones answer to the bones of our wrist. 
The metacarpus is composed, in adult birds, of a singe bone 
of complex shape and nature. It bears a more or less rounded 
articular surface at its proximal end, which is somewhat ex- 
panded ; for the greater part of its extent, however, it consists 
of a long, stout, cylindrical bone, generally separated by an 
interspace from a more slender and curved, similarly elongated, 
bony bar situated externally to the other. This slender external 
bar answers to that bone of the fleshy part of our hand—or 
‘‘ metacarpal” bone—which supports our middle finger. The 
stouter bar answers to that bone of the fleshy part of our hand 
which supports our fore finger or index digit, and it is therefore 
the ‘metacarpal of the index.” 
On the inner side of the base of this metacarpal is a small 
prominence truncated distally. This answers to the bone of the 
fleshy part of our hand which supports our thumb or pollex, and 
it is therefore the metacarpal of the pollex. In no existing 
adult bird are the metacarpals separate. 
