Charles R. Bardeen 329 
special slip of the muscle and terminates in the proximal portion of the 
middle third of the m. tensor fascize late. It gives branches of innerva- 
tion to the gluteus minimus muscle, to the lateral portion of the gluteus 
medius muscle and to the tensor fascie late. The fibres of the ascend- 
ing branch always arise from the plexus lower down than those of the 
transverse branch. Sometimes it arises as a separate branch from the 
first sacral nerve. It may then pass through the substance of the piri- 
formis muscle and be associated with the nerve to the piriformis muscle. 
Nerve to the piriformis muscle-——Very commonly the nerve to this 
muscle may arise from a loop connecting the first and second sacral 
nerves, but more often the branches arise directly from the first or second 
sacral nerve and pass into the substance of the muscle in the middle third 
between the tendons. The ascending branch of the superior gluteal nerve 
may send a ramus to the piriformis muscle. J have never seen a branch 
from the third sacral nerve to the piriformis such as those described by 
Weber, Hildebrandt, Valentine and Henle. 
V. THE GLUTEUS MAXIMUS AND THE SHORT HEAD OF THE BICEPS. 
The studies in comparative anatomy of Ranke, 97, Klaatsch, 02, and 
others have gone to prove the close morphological association of the 
gluteus maximus and the short head of the biceps. 
It seems probable that both the short head of the biceps and the gluteus 
maximus are represented in the urodeles by the ilio-(femoro)-fibularis and 
in reptiles by the ilio-fibularis muscle which is supplied by the peroneal 
portion of the sciatic. In the mammals the proximal attachment of this 
musculature has extended well into the caudal region from the ilium. In 
the monotremes it is represented by a muscle which extends from the caudal 
region to the foot and in Echidna lies posterior to and does not cover the 
other glutei (Westling). In most of the higher forms it is divisible into 
three muscles, the superficial gluteus, or gluteus maximus, the femoro- 
coccygeus (Leche), and the gluteo-crural (Klaatsch). The superficial glu- 
teus is inserted into the femur or into the fascia of the thigh. The femoro- 
coccygeus is inserted into the shaft of the femur, and the gluteo-crural into 
the fascia of the leg or into the fibula. The superficial gluteus and the 
femoro-coccygeus are not infrequently fused to form the gluteus maximus. 
The gluteo-crural is absent in some forms. In most mammals it extends as 
the tenuissimus from the caudal vertebre or the gluteal fascia to the leg. 
In man and a few of the higher primates it arises from the femur and be- 
comes applied to the tendon of the long head of the biceps to form the short 
head of this muscle. Klaatsch, o2, has given an especially valuable account 
of the gluteo-crural muscle. See also Windle and Parsons, oo. 
In man the gluteus is not infrequently found divided into two portions, a 
condition normal in the embryo. The short head of the biceps not infre- 
