1882.] ANATOMY OF ERETHIZON DORSATUS. 285 
The pectineus extends from the brim of the pelvis dorsad of the 
origin of the third part of the adductor; it is inserted into the 
femur just below the lesser trochanter. 
The vastus externus is very large, its origin extending right up 
to the summit of the great trochanter. 
The vastus internus also extends very high up, namely up to the 
neck of the femur, dipping in within the insertion of the psoas. 
The erureus extends up to the neck of the femur, and is very im- 
perfectly separated from the vastus internus. 
The rectus femoris has the usual origin and insertion. 
The tibialis anticus is very large, but does not take origin from 
the femur; it arises from the head of the fibula and the upper third 
of the tibia. Below its ends are two tendons, one of which is 
inserted into side of the proximal end of the metatarsal of the 
hallux, while the other goes to the plantar surface of the ectocunei- 
forme. 
The extensor longus digitorum arises by a tendon from the femur 
external to its rotular surface. It is a slender muscle, and sends 
tendons to the four outer digits. 
The extensor longus hallucis is very slender and small, arising only 
from the distal third of the fibula. 
The ewtensor brevis digitorum arises a8 usual, and sends tendons 
to the four outer digits. 
The peroneus longus is the most external of the peronei muscles, 
and arises from the head of the fibula. Passing behind the 
external malleolus, it proceeds to the metatarsal of the hallux as 
usual. 
The peroneus brevis arises from the antero-external aspect of the 
fibula. It is muscular down to the level of the malleolus, and ends 
in a very strong tendon (the largest of the peronei tendons), which 
is inserted into the proximal end of the fifth metatarsal. 
The peroneus quinti digiti is very slender, both as to its muscular 
belly and its tendon. It arises from the outside of the fibula, 
beneath the peroneus longus and behind the peroneus brevis, and in 
contact with the flexor longus hallucis. It becomes tendinous above 
the external malleolus; and its slender tendon is inserted into the 
proximal part of the proximal phalanx of the fifth digit. 
The gastrocnemius has but the two normal heads, and is inserted 
into the calcaneal tuberosity. 
The soleus is very large and fleshy; it arises from the outer side 
of the upper two thirds of the fibula, and joins the tendo Achillis. 
The plantaris takes origin from the pit on the outer side of the 
external condyle of the femur, beneath the external lateral ligament. 
It ends as in the Agouti’. 
The popliteus is as in the Agouti. 
The flewor longus digitorum is a large muscle arising from the 
tibia beneath the popliteus ; its tendon passes in a groove behind the 
internal malleolus, superficially to that of the tibialis posticus. It 
1 P.Z. 8. 1866, p. 414. 
