ANATOMY OF THE LEMUROIDEA. 45 
the middle of the forearm, these again subdividing into four tendons, besides the extra 
short tendon of union with the flexor profundus, which is given off from the inner or 
back part of the ulnar division. 
In our dissection of this species we find the flexor sublimis to be a very large muscle 
indeed, and its divisions somewhat different from those described by Owen. Its dif- 
ference of size, indeed, as compared with the same muscle in Lemur and Galago, is 
remarkable. It may be described as consisting of two portions. The first, a most 
superficial portion (which is the wider of the two), arises from the internal condyle, 
intermuscular fascia, and outer border of the tibia for its upper half. It sends a single 
strong tendon to the fourth digit. The second and more rounded or compressed 
portion arises also from the inner condyle, below the last, but has no origin from either 
bone of the forearm. At the lower third of the forearm it is divisible into two bellies 
and their tendons; the middle tendon (derived more from the radial half) joins the 
deep flexor muscle; the radial tendon subdivides into two, going to the index and third 
digits respectively. The ulnar tendon supplies the fifth digit only. (See woodcut, 
fig. 17.) 
FLEXOR PROFUNDUS DIGITORUM.—A considerably larger muscle than the flexor sub- 
limis. It arises from the upper two-thirds of the anterior surface of the ulna, the 
interosseous membrane, the coronoid process, and the adjacent part of the ulna external 
to the insertion of the brachialis anticus. It is from this last part that the slip comes 
which joins the flexor longus pollicis. The muscle ends in a strong tendon (smaller, 
howeyer, than that of the flexor longus pollicis) which at the wrist receives on the 
radial side of its superficial surface the delicate tendon (woodcut, fig. 13**) from the 
flexor sublimis. Immediately after this it unites with the tendon of the flexor longus 
pollicis, and with it forms the deep and perforating tendons of the digits, taking, 
however, little, if any, share in the formation of that of the pollex. 
In Galago crassicaudatus and in G. allenii this muscle may be described as having 
three distinct heads of origin. The most internal and slightly the largest muscular 
bundle (PI. IV. fig. 14, #p.d') arises from the posterior and internal surface of the 
olecranon process from the internal condyle and intermuscular fascia. Muscular fibres 
proceed as far as the upper end of the upper third of the forearm on the ulnar side; but 
on the radial margin there is a strip of tendon as high as the lower end of the upper 
third. A separate tendon goes as far as the wrist, where it joins the broad common 
tendon of the three portions of the muscle. 
The second head of origin (the smallest) (Pl. IV. fig. 14, /.p.d*) lies to the outer 
side of the last, and arises by a short tendon from the front aspect of the inner condyle, 
close to the perforation. The belly of this portion goes fully as far as the middle of the 
forearm, and ends in a narrow, delicate tendon, which joins the broad common tendon 
above the wrist upon its inner side. 
The third portion of the flexor profundus (Pl. IV. fig. 14, F.p.d*), as large as the 
G2 
