58 
aspect of the entocondyle. They are partially distinct as far as 
the sesamoid bone, into which they are inserted, partly fleshy, 
partly tendinous, rather in front of the other two portions. 
Ulnaris proprius (f. dig. 3 in figures) arises from the whole of 
the hollow inner surface of the large olecranon and from the 
inner surface of the proximal half of the ulnar shaft. It is 
partly overlapped by the condylar heads of the muscle, and 
largely by that of the flexor carpi ulnaris. It is inserted into 
the proximal end of the palmar sesamoid by a stout rounded 
tendon, side by side with, and on the ulnar side of, the insertions 
of the condylar heads, though slightly on a deeper plane. The 
tendon of insertion is continued up in the substance of the 
muscle ; and into the superficial aspect of the tendon, in the 
upper part of the forearm, are inserted many short fleshy fibres, 
which arise from the intermuscular septum between the muscle 
and the overlying flexor carpi ulnaris. 
The remaining portion—vradialis proprius (f. dig. 4 in figures) 
—is deepest of all. It takes origin by fleshy fibres from the 
shaft of the radius, extending up as far as the insertion of the 
biceps, and downwards as far as the lower end of the radius. It 
is inserted into the deeper aspect of the proximal end of ihe 
palmar sesamoid, close to its radial corner. 
The distal extremity of the palmar sesamoid gives origin to 
two short, very thick, and rounded tendons; and a third, more 
slender, tendon arises from the radial border of the bone, close to 
its distal end. The latter passes on to the palmar aspect of the 
second digit, and courses distally in front of its proximal phalanx, 
to whose palmar surface it is secured by a fibrous ring. It then 
passes on to be inserted into the palmar aspect of the base of the 
terminal phalanx. 
The other two thicker tendons are inserted into the palmar 
aspects of the strong ungual phalanges of the third and fourth 
digits respectively. 
A tendinous vinculum connects the medial with the indicial 
tendon (fig. 15, v2.). 
Lumbrical slips are entirely absent. 
Windle* has shown that where the flexor profundus attains a rela- 
tively great development, the flexor sublimis is proportionately re- 
duced, and this he states to be the case in many of the Carnivora, and 
some of the Marsupialia. 
Such a condition is typically illustrated in the case of Dasywrus, 
where flexor sublimis was found by MacCormick+ to consist of a 
slender tendon lying in a shallow groove in front of the great flexor 
tendon, and arising from the front of the upper part of the latter. 
This author describes the great deep flexor mass in four parts, the first 
* |xvili:, page 73. + xxxvi.. page 132. 
b) fo} > fo} 
