64 PROFESSOR OWEN ON THE AYE-AYE. 
The tendon of the fasciculus representing the flewor longus pollicis has an adhesion 
to the supplementary carpal ossicle and attached part of the transverse fascia, beyond 
which adhesion (Pl. XXII. fig. 1, s+) it sends the more distinct tendon to the pollex ; 
but the effect of this attachment is to oppose, not the pollex only, but the pad at its 
outer base, which is supported by the supplemental ossicle (Pl. XXI. fig. 17, 0) in the 
grasping act, when the radial is opposed to the ulnar side of the hand. The fleshy part 
of both flexors, but especially of the deeper-seated muscles, continues far on towards the 
hand, as in other Lemuride, and also as in the climbing Rodentia, thus enabling the 
muscles to continue their action as finger-benders in the bent position of the hand itself’. 
The tendons of the deeper flexors are thicker than those of the superficial flexors ; but 
both those of the middle digit are very slender. 
The pronator quadratus rises from the fore part of the lower fourth of the ulna. Its 
fibres pass obliquely outwards and downwards, to be inserted into the corresponding fore 
pert of the radius. Both the pollex and minimus have their abductor and adductor 
muscles and short flexors. ‘The tendons of the deep flexors give attachment to four 
lumbricales. Some of these minor muscles of the digits are noticed in the descrip- 
tion of the Plates. 
Muscles of the lower limbs.—The psoas magnus (Pl. XXIV. fig. 1, 1) presents a character 
of unusual length, corresponding with that of the lumbar region, from which it chiefly 
arises, its highest or foremost origin being from the last dorsal vertebra. An inner 
and superficial portion (a2) may be recognized as an ill-defined psoas parvus, but 
becomes distinct below where it is inserted into the ileo-pectineal ridge. An outer por- 
tion (b) more especially unites itself with the iliacus internus, and, with the main body 
of the psoas, passes on to be inserted into the lesser trochanter, the unusual prominence 
of which relates mainly to the power of this great flexor of the trunk on the thighs and 
reciprocally. 
The iliacus internus (7b. 2) is a long and thin or flat muscle from the fore part of the 
ilium, behind and exterior to the psoas, with which, especially the outer fasciculus, 
it unites below, fora similar insertion in the lesser trochanter. 
The tensor vagine femoris (Pls. XXIV. & XXYV. fig. 1,5) is represented by a small 
external fasciculus from the anterior superior spine of the ilium, which extends into the 
fascia covering the fore and outer part of the thigh. 
The sartorius (Pls. XXTV. & XXV. 15) is a long, flat, rather broad muscle, arising 
fleshy between the iliacus internus and ecto-gluteus* from the anterior border of the 
ilium, passing obliquely across the inner side of the thigh, slightly expanding to be 
attached to about an inch of the upper part of the spine of the tibia (Pl. XXV. fig. 2, 1s) 
and to a thin fascia covering the knee-joint (Pl. XXIV. f). 
The gracilis (ib. 14) rises fleshy from the whole of the symphysis pubis, and is similar 
* Vrolik, op. cit. p. 45. 
* Gluteus mavimus of anthropotomy. (See ‘ Osteology of Chimpanzees,’ &c., p. 15.) 
