266 Rev. S. Haughton on the Muscular Mechanism 



seen. The weight of the fleshy belly of the rectus femoris pro- 

 per is 7\ oz. 



13. M. sartorius. This important and remarkable muscle 

 arises from the anterior portion of the ilium (fig. I.), and from 

 some of the spines of the lumbar vertebrae, and, passing in the 

 usual manner across the inner aspect of the thigh, is inserted 

 into the inner side of the ligamentum patellae and into the top 

 of the tibia. Its weight is 18 oz. 



14. M. iliacus has a lozenge-shaped origin on the anterior 

 portion of the ilium, between the opponens quadrato femoris 

 and glutaeus minimus (fig. I.). Its insertion into the femur is 

 shown in fig. III., at a point which must be supposed to represent 

 the lesser trochanter. Its weight is If oz. 



15. M. gracilis arises, like the semitendinosus, from the tuber 

 ischii and from the lower half of the ligament joining it to the 

 posterior spine of the ilium, and is inserted into the fascia of 

 the inner side of the knee-joint. Its weight is 4^ oz. 



16. M. adductor magnus arises from the anterior half of the 

 ischial line (fig. I.), and is inserted into the upper margin of the 

 condyloid pit at the back and inner side of the femur (fig. II.). 

 Its weight is 4| oz. Its fibres were pale and fatty in the speci- 

 men dissected by me. 



17. M. pectinaeus arises from the pectineal point (fig. I.), 

 is inserted into the tibia on the inner side of the knee, and is 

 intimately connected by muscular fibres with the vastus internus 

 (2). Its weight is 4 oz. The blending of the fibres of this 

 muscle with those of the vastus internus, a portion of which, 

 like this muscle, terminates directly in the tibia, is not to be 

 forgotten in considering the mechanical action of the muscles 

 on the hip- and knee-joints. 



18. M. quadratus femoris has an origin on the ischial line 

 just below that of the adductor magnus, and an insertion, of a 

 linear shape, in the back of the upper portion of the femur, 

 shown in fig. II. Its weight is 2| oz. 



19. M. opponens quadrato femoris. This muscle I have so 

 named because it is met with in many animals as the direct 

 opponent of the quadratus femoris. In the muscular systems 

 of the Ostrich and Lion this antagonism between the muscles is 

 very striking. It is found occasionally in human subjects, and 

 is described by Harrison under the name of M. ilio-capsularis. 

 While we had the Ostrich in the dissecting-room of Trinity 

 College, a human subject was brought in, which had the ilio- 

 capsular muscle fully developed ; and my attention was called to 

 it by Dr. Bennett. 



In the Ostrich the M. opponens has an origin on the anterior 

 surface of the ilium, between those of the Mm. sartorius, rectus, 



