ARTERIES OF HUMAN LOWER EXTREMITY 93 
Branches. The a. recurrens tibialis anterior represents NG 
terminal portion of the a. perforans cruris (p. 68). 
The a. malleolaris anterior medialis is derived from the r. 
coronarius of the a. interossea which arises shortly before the 
stage of 18 mm. 
A. tibialis aniertor, pars distalis. This embryonic artery 
arises at about the stage of 15 or 16 mm. Its course is identical 
with that of the fourth part of the a. tibialis anterior of the 
adult. 
A. tibialis posterior. The part of this artery proximal to the 
origin of the a. peronaea is the product of the union between the 
a. tibialis posterior superficialis and the a. peronaea posterior 
superficialis. The remainder of the vessel is a survival of the 
part of the stem of the a. tibialis posterior superficialis proximal 
to the point at which it is joined by the medial terminal branch 
of the a. peronaea posterior superficialis. 
Branches. The a. peronaea is described on page 90. The 
a. malleolaris posterior medialis and the r. communicans are 
derived from the embryonic r. coronarius malleolaris medialis of 
the a. interossea (p. 73). 
A. tibialis posterior superficialis. The course of this artery, 
which arises shortly before the stage of 14 mm., is described on 
page 70. 
The whole of the a. tibialis posterior superficialis persists in 
the adult life. In combination with the a. peronaea posterior 
superficialis, the more proximal part of the artery forms the 
part of the a. poplitea in contact with the m. popliteus and the 
part of the a. tibialis posterior proximal to the origin of the a. 
peronaea.- The more’ distal part of the artery persists as the 
portion of the a. tibialis posterior beyond the origin of the a. 
peronaea and as the a. plantaria medialis. 
The relation of the part of the a. tibialis posterior super- 
ficialis which forms the a. tibialis posterior of the adult to the 
n. tibialis is discussed on page 84. 
Rete dorsale. The dorsal rete of the embryonic arises from 
the r. perforans tarsi. It forms all the arteries which are 
distributed upon the dorsum of the adult foot. 
