The Gluteal and Femoral Muscles in a Marmoset. 169 



In the case of each muscle I have carefully noted the 

 nerve supply, and have, further, referred each nerve to its 

 origin from the spinal nerves. This has been done under 

 the conviction that a consideration of muscles unassociated 

 with an examination of their nerve supply is deprived of at 

 least half its potential value. The admirable papers by 

 Champneys on the Chimpanzee and Cynocepliahis anuhis, and 

 by Hepburn on the Anthropoid Apes, would have been far less 

 valuable contributions to anatomical literature had they not 

 included both. 



I. The Gluteal Muscles. 



Gluteus maximus (ecto-gluteus) was, in the gluteal region, 

 a thin, flat muscle, consisting of two parts, an upper and a 

 lower. The two parts joined very shortly after their origin 

 to form a thick, more or less rounded, fleshy mass in the 

 thigh, so that, although the muscle was very thin in the 

 gluteal region, yet, taken altogether, it was the largest of the 

 three glutei. The upper or cephalic portion of the muscle 

 took origin from the posterior lamella of the lumbar fascia, 

 covering the muscles lying in the vertebral groove, and 

 covering also a muscle (ilio coccygeus) which extended from 

 the postero-superior spine of the ilium to the lateral aspect 

 of the sacrum and the caudal vertebrae. This part, by its 

 upper fibres, was inserted into the posterior surface or border 

 of the great trochanter, and by its lower fibres it joined the 

 lower division of the muscle. 



The lower or caudal portion of the muscle arose from the 

 lateral aspect of the upper caudal vertebrae, ventral to the 

 ilio coccygeal muscle mentioned above and other "supra- 

 caudal" muscles by which it was overlaid. The upper 

 margin of the lower portion was at a lower as well as a more 

 ventral level than the lower border of the upper piece at its 

 origin, so that there was a small gap left between them before 

 they joined, and through this gap there passed the ilio 

 coccygeal and supracaudal muscles which lay subjacent to 

 the upper portion, but superficial to the lower. The lower 

 portion was joined by the lower fibres of the upper, and was 

 inserted by fleshy fibres into the lower part of the posterior 



