The Gluteal and Femoral Muscles in a Marmoset. 181 



of the insertion of gracilis. There was no tendinous inter- 

 section. 



In animals generally there are normally, according to 

 Parsons, two heads of origin which unite in the upper part 

 of the thigh, and where they unite there is a tendinous 

 intersection. According to Leche, in Prosimia, except 

 Cheiromys (Alix, 18), and in Primates, the caudal head is 

 absent. The tendinous intersection seems to be usually 

 absent. 



In lemurs (2) the muscle arises in common with biceps ; 

 there is no caudal origin. It is inserted in common with 

 gracilis. In Cheiromys (19), however, there is an origin 

 from the second caudal vertebra. In Mickis rosalia both 

 origins are present, and insertion is lower than in man, and 

 is under cover of the gracilis insertion. In Hapale penicillata 

 (9) the semi-tendinosus is combined with semi-membranosus, 

 and they are represented only by a thin muscle, which has 

 both ischial and caudal origins, and is inserted entirely with 

 gracilis. In other Primates described by Bischoff the muscle 

 was strong and fleshy, and there was no tendinous inter- 

 section. The insertion was low down on the tibia. In 

 Cynocephalus anuhis (7) there was no tendinous intersection, 

 and there was no caudal origin. The insertion was partly 

 into the anterior tubercle of the tibia, and partly in common 

 with gracilis into the fascia more than half way down the leg. 



In the Anthropoids (8) there is no caudal origin. In the 

 gibbon, the orang, and the chimpanzee there was a faint 

 tendinous intersection. In the chimpanzee it was fused 

 with the upper surface of semi-membranosus. 



Semi-membranosus consisted of two parts imperfectly fused 

 together. One part was the semi-membranosus proper, the 

 other represented the presemi-membranosus of some animals, 

 or that part of the adductor magnus of man which gets its 

 origin from the ischial tuberosity. The semi-membranosus 

 took origin by tendinous fibres from the lower end of the 

 ischial tuberosity touching the origin of semi-tendinosus. 

 The presemi-membranosus arose by fleshy fibres from the 

 lower edge of the ischial ramus. 



In the thigh the muscle as a whole lay under cover of 



