124 THE OSTEOLOGY AND MYOLOGY 



GlutctMS minimus. — (Fig. 32, I.) Smallest and most anterior of the three ; the only one 

 that arises wholly from the ilium. It takes origin from the common tendon at the tip of 

 the ilium, from the prominent ridge along the anterior border of the bone, and from the 

 flat expansion of bone inside this ridge near the head of the femur. Its anterior border 

 meets and blends with that of the glutieus maximus, thus enclosing the medius, and is in 

 apposition with the iliacus. It has an extensive insertion into the apex of the great tro- 

 chanter ; its action is much the same as that of the foreoroino;. 



Femoro-coccygeus. — (Fig. 32, h.) In the course of numerous dissections I have found 

 considerable variation in this muscle — if it really be a distinct one. Sometimes it is 

 scarcely demonstrable as distinct from the glutoeus maximus ; its aponeurosis of caudal 

 origin being directly continuous with that of the glutoeus ; its fibres lying in precisely the 

 same plane ; its anterior border scarcely separable from the posterior border of the glutajus ; 

 its femoral insertion appearing like a direct continuation, along the bone, of the gluta3al in- 

 sertion. In such cases it expends itself upon the femur without reaching the head of the 

 tibia, or, at most, only a fascial or aponeurotic extension attains the knee. When most 

 distinct it is separated by a delicate fascia, or a cellular interspace, from the posterior border 

 of the glutoeus ; and near its origin its fibres may not lie quite parallel with, or even may 

 overlap, those of the glutseus. It then proceeds, with little or no proper attachment to 

 the femur, to the leg ; its posterior border runs along the upper border of the biceps ; its 

 crural insertion is by a broad aponeurosis, common to it and to the biceps, into the fascia 

 over the leg, just below the knee. The muscle is always flat and very thin ; at its origin it 

 may be an inch or more broad ; it narrows before passing the trochanter, and in the rest of 

 its extent it is only a third or a fourth of an inch wide. It extends the thigh and flexes 

 the leg ; secondarily, it subserves somewhat to the lateral motion of the tail. Either this 

 muscle, or the one below described as "cruro-coccygeus," is the homologue of what is called 

 the "musculus accessorius a cauda ad tibiam tendens," in the Oiiiithorhynchus. 



Pyriformis. — This muscle is of comparatively large size, and has the shape that has 

 given it its name in anthropotomy. It is covered by the glutasus medius, appearing just 

 under the posterior edge of this, when the maximus is reflected. It arises from the trans- 

 verse processes of two or three vertebrae, immediately following the synchondrosis, running 

 obliquely outward and backward across the sciatic notch and body of the ilium, in front of 

 the origin of the ischio-coccygeus, and across the hip joint, to be inserted into the very 

 apex of the troohnnter mnjor, in intimate relation with tho tendon of the glutitvis medius, 

 but distinct from that of the obturator internus. 



Quadratus femoris. — Of much the same shape and relative size as in man, arising from 

 the ischium next above the adductor, with a broad, fleshy insertion into the back and lower 

 part of the trochanter major, and smooth space between this and the trochanter minor. It 

 extends and everts the thigh. 



Obturator externus. — Much larger than the other ; a thick rounded muscle, correspond- 

 ing to the contour of the ischium and pubes, occupying the surface of the bone and fora- 

 men. It is inserted by a stout, narrow tendon, somewhat terete, into the lower part of the 

 digital fossa. 



Obturator internus. — A thin plane of fibres, rounded in contour, occupying and arising 

 from the whole inner face of the bone, and obturator membrane. Its tendon, which has 

 decided traces of the peculiar digitated structure so beautifully shown in our own, curves 



