66 PROFESSOR OWEN ON THE AYE-AYE. 
The mesogluteus (Pl. XXV. fig. 3,5) is a long and very thick muscle, arising from 
the outer side of the ilium and the fascia covering the sacrum, the fibres converging 
to be inserted into the upper part of the great trochanter. 
The entogluteus arises from the lower part of the ilium and adjoining part of the 
ischium, to near the tuberosity, and is inserted into the great trochanter on the inner 
side of the mesogluteus. The great ischiatic nerve and artery lie between the posterior 
margins of these muscles. The entogluteus is attached to the underlying part of the 
capsule of the hip-joint. 
The vastus externus (Pl. XXV. figs. | & 3, 7).arises from the fore and under part of 
the trochanter major, by a short tendon, visible on its outer side only. It rapidly swells 
into a large fleshy mass, forming the outer part of the thigh, and converges to a flattened 
tendon, which is closely blended with the capsule of the knee-joint as it passes to its 
insertion into the upper and outer part of the patella. It sends off no fleshy fasciculus 
to the rectus femoris, as observed by Vrolik in Stenops’. 
The rectus femoris (Pls. XXIV. & XXV. figs. 1-3,15) rises by a strong round tendon from 
the upper part of the acetabulum, and by a shorter tendon (fig. 3, 6) from the inferior 
spine of the ilium. The muscle becomes fleshy at the junction of these, is fusiform, the 
strong subdepressed tendon being inserted into the upper part of the patella. 
The vastus internus (Pls. XXIV. & XXV. figs. 1 & 2, 18) arises from the fore part of 
the great trochanter, becomes attached by a fascia to the inner side of the rectus femoris, 
developes a slender tendon on that side, which goes to the ligamentum patelle, and then 
spreads into a thin fascia attached to the inner side of the knee-joint and ligamentum 
patellz. 
The crureus (Pl. XXV. figs. 2 & 3, ») arises from the whole of the inner and fore 
part of the femur, quitting the bone only at the lower end to spread over the upper part 
of the capsule of the knee-joint prior to being inserted into the corresponding part of 
the patella. The outer division of the crureeus (fig. 3, 19) is rather a distinct muscle, 
which might be termed the deep-seated vastus externus: it arises from the fore and 
outer part of the femur to the condyloid expansion, and is inserted by a fascia into the 
outer part of the ligamentum patella and capsule of the knee-joint. 
The pectineus (Pl. XXV. fig. 2, 1) arises from the upper part of the pubis, near 
the symphysis, and is inserted below the lesser trochanter. Beneath it are strong and 
thick gemelli, converging from their origin on the anterior surface of the pubis and 
ischium to the interspace between the small and large trochanter. 
The gastrocnemius (Pls. XXIV. & XXV.+) arises by the usual outer (fig. 2, 27, a) 
and inner (fig. 2, », 6) heads from the back part of the corresponding condyles, 
the tendons being strengthened each by a sesamoid ossification. The outer head 
principally receives the accession of fibres from the upper part of the fibula, called soleus 
(fig. 3,28) ; after which they combine into a single mass, which becomes tendinous on the 
‘ Op. eit. p. 46. 
