452 E. C. MacDowell. 
The Soleus is the largest muscle that enters the Tendo Achillis, 
It has no tibialhead. This is true for the chimpanzee, the baboon, 
and the macacus. In the chimpanzee, the fibers are inserted all 
along the inner surface of the Tendo Achillisas far asits insertion. 
The tibial head was absent in the chimpanzee and in 
the baboon of Michaélis. He said that it probably is included in 
the gastrocnemius lateralis when itis said to belacking. MeMurrich 
(04) suggests that the plantaris represents the plantaris pro- 
fundus III of Amphibian, while Hisler had regarded it as a deriva- 
tive of the gastrocnemius lateralis. 
All the bellies joined to the Tendo Achillis are separate from 
their origins to their insertions, a condition frequently found in 
man (Bardeen). Muscle fibers are incorporated with the Tendo 
Achillis for its whole length. Michaélis found this to be the 
case in his chimpanzee. The calf is slim, presenting nomore thaa 
a slight swelling. This is in sharp contrast to the well developed 
human calf, which occurs as a result of man’s mode of locomotion. 
The Tibialis anterior has two bellies in both chimpanzee and 
baboon. In the former, it arises from the anterior external sur- 
face of the tibia along its proximal two thirds. One third the 
distance from its origin, the muscle divides. The internal por- 
tion is the larger; its fibers are inserted into the deep aspect of 
a strong, round tendon, which is inserted into the internal palmar 
aspect of the distal third of the cuneiform bone. The external 
portion, whose tendon is half as large as the first one, is inserted 
into the internal palmar aspect of the base of the first metatarsal 
bone. This separation of the tendon, inserted partly on the cunei- 
form, and partly on the metatarsal, has been found as a variation 
in man (Le Double). In his baboon, Michaélis, found that the 
tendon divided just before being inserted upon these bones. In 
his chimpanzee, it divided at the origin. Beddard and Vrolik 
described such a separation. Owen describes the tendon to the 
metatarsal bone as a separate muscle with no homologue in man. 
Ruge says the division is well known and that Bischoff has found 
three parts. 
The Peroneus longus in the chimpanzee arises from the head of 
the fibula, from the intermuscular septum between it and the 
