108 



THE BONES. 



Fig. 67. 



The superior horder articulates with the radius ; the inferior border with the 

 metacarpal bones. 



The lateral borders are nearly flat ; above and behind the external border is 

 remarked a considerable eminence, formed by the 

 bone which will be hereafter studied as the super- 

 carpal bone (pisiform or trapezium). 



In the carpus of the Horse are seven or eight 

 bones, which are disposed in two superposed rows. 

 The superior row comprises four bones placed side 

 by side, and designated by the numerical names of 

 first, second, third, and fourtli, viewing them from 

 without to within. The inferior row has only 

 three, which are named in the same manner. 



In applying to them the names proposed by 

 Liser, we have, in the upper row — 



1. The pisiform, or supercarpal bone. 



2. The cuneiform bone. 



3. The lunar bone. 



4. The scaphoid bone. 

 In the inferior row — 



1. The unciform bone. 



2. The magnum bone. 



3. The trapezoid bone. 



4. The trapeziiun (not constant). 

 The description of these bones is most simple, 



and may be made in a general manner for all. Thus, 

 with the exception of the supercarpal bone, they 

 are solid, nearly cubical in form, and exhibit on 

 their periphery : 1. Articular surfaces. 2. Surfaces 

 for insertion. 



The articular surfaces are small, flat, or slightly 

 undulating facets, distributed on the superior, in- 

 ferior, and lateral faces ; none are found in front 

 or behind. The superior and inferior faces are 

 entirely occupied by a single facet, which responds 

 either to the radius, the metacarpals, or to the bones 

 of the other row. The lateral facets are always 

 multiple, and in contact with the bones of the same 

 tier ; they do not exist, of course, on the outside 

 of the bones at the ends of each row. 



The surfaces for insertion are absent on the 

 superior and inferior faces ; they separate, in the 

 form of roughened depressions, the lateral articular 

 facets. Before and behind, they are covered by 

 more or less marked rugosities. 



Bones of the Upper or Antibrachial Row 

 (Figs. 68, 69). — The first, or os pisiforme, is outside 

 the row ; it is situated above and behind the carpus, whence its name of super- 

 carpal bone, by which it is usually known in veterinary anatomy. This bone, 

 which merits a special description, represents a disc flattened on both sides. 



RIGHT ANTERIOR FOOT OR HAND 

 OF A HORSE. 



1, Radius; 2, grooves for the ex- 

 tensor of the phalanges; 3, 

 scaphoid; 4, lunar; 6, cunei- 

 form ; 6, pisiform ; 7, mag- 

 num ; 8, unciform ; 9, great 

 metacarpal; 10, small meta- 

 carpal ; 11, sesamoid bone ; 12, 

 suffraginis ; 13, coronary; 14, 

 navicular; 15, pedal ; 16, basi- 

 lar process. 



