////: .\\rri: n in /./w/;>. 



77 



Fig. 44. 



process the <>l>;-r<in<'it flattened .n l>o(h siilcs. and presenting : 1. An 

 sisil face, slightly convex; li. An intcnuil excavated fiico ; 3, An 



anterior border, thin and sharp superiorly, 



notched below to for inthe /</.-/// </<////:' un 



articular surface concave from above down- 

 wards, rounded from one side to the other, 



which corresponds with the humeral cavity, 



and is surmounted by a salient prolongation 



named the beak of the olecranon ; 4, A con- 

 anil smooth posterior border; 5, The 



mniunit, a kind of thick roughened tuberosity 



which terminates the olecranon above, and into 



which arc inserted the extensor muscles of the 



inn. 

 At its inferior extremity, the ulna ends, 



towards the lower fourth of the principal por- 

 tion of the fore-arm, in an acute point, and 



sometimes by a small knob (capittdum ulnie). 



It is not rare to see it prolonged, especially 



in the Ass and Mule, to the inferior external 



tuberosity of the radius. This tuberosity then 



appears to belong to it, at least in part; and 



all that portion which is situated behind its 



vertical groove might be justly considered as 



belonging to the ulna. 



Structure Kii'l development. The ulna con- 

 tains much compact tissue, even in the region 



of the olecranon; it is also very solid. It is 



an imperfect bone, developed from two centres 



of ossification only, one of these being for the 



a] MX of the olecranon. 



FOltE-FOOT 



HAND. 



The anterior foot, or hand, is the region 

 which presents the greatest differences when it 

 is inspected in the various individuals of the 

 animal series. Nevertheless, in all the mam- 

 malia the constitution of the hand is funda- 

 mentally the same, and may be divided into 

 three sections : the carpus, metacarpus, and 

 pJialangeal region. 



The hand is formed by five parallel or 

 quasi-parallel rays that constitute the digits, 

 each of which is effectively or virtually com- 

 posed of tir,, aiijn rposed carpal, a metacarpal, 

 and //</'< phalangeal bones, forming altogether 

 the ili'j'tt, properly so called. But tin 

 composition. < >iablished through the labours 

 of MM. Joly and Lavocat, is rarely found to 

 be realised in a complete manner. 



TOOT OF A 



Kalis; _'. CI-MMV.' for the an- 

 terior extensor of the jihalan- 

 *' ipiiiii'lcs ; 4, Lunare ; 

 .">. Cuneiform ; >>, Traix'/'mn -. 

 7, Magnum ; 8, Un. ii'orm : '.'. 

 Metacarpal ; In, Small in.-ta- 

 carpal ; 11, ScsanioM I. 

 Sull'rai;ini> ; l:!, Coronary ; 14. 

 Navii-ular ; i:>. l\-<l.il ; jii, Its 

 aln. 



The following is what is presented in the hand of Man, who is the most 

 1 Tin; greater tigmoid cavity of Man. 



