232 MYOLOGY. 



Gluteus externus. 

 Glutens maximus. 



Gluteus irrtevnus. 

 Rectus parvus. 



Obturator externus. 

 Obturator internus. 

 Pyriformis. 

 Gemellus anticus. 



Gemellus posticus. 



GLUTEUS EXTERNUS. 



(Uio-trochanterius Meditis.) 



(PL. II. 56; FIG. 84. 6.) 



This is a V-shaped muscle situated on the external part of the 

 croup, its fibres converging downwards. It consists of a muscular 

 and an aponeurotic portion ; the former is double, the parts cqn- 

 verging and ending in a flat tendon ; the aponeurotic joins the 

 fleshy portion posteriorly, and is hidden under the triceps abduc- 

 tor femoris. 



Origin. The anterior portion arises from the anterior spine 

 of the ilium, the posterior from the second and third sacral 

 spines ; also from the gluteal fascia. 



Insertion. To the trochanter minor ; the aponeurotic portion 

 reaches the tuberosity of the ischtum and the sacro-sciatic liga- 

 ment. 



Relation. Externally with the gluteal fascia ; anteriorly with 

 the fascia lata ; posteriorly with the triceps abductor; internally 

 with the maximus. 



Action. It abducts the thigh. 



GLUTEUS MAXIMUS. 



(Ilio-trochanterius Magnus.) 



(PL. III. 30; FIG. 84. c.) 



This is a very large muscle occupying the iliac dorsum, and 

 stretching forwards over the lumbar region ; it is fleshy and thick 

 in its centre, terminating in two tendons. 



Origin. From the iliac shaft, crest, dorsum, and spines, 

 anterior and posterior, the side of the sacrum, the sacral and part 

 of the sacro-sciatic ligaments, and the tendinous envelope of the 

 longissimus dorsi as far forward as the last rib. 



Insertion. By two tendons, one to the summit of the tro- 

 chanter major, the other anteriorly to the crest below the con- 



