240 



ANATOMY OF VERTEBRATES. 



156 



Muscles of pelvis, Emys Europaa. xxxvm. 



parts of the hypo- and xiphi-sternals, and is inserted into the 

 outer process of the; pubis. The retro lie us pdvim, ib. 44, arises 

 from the posterior half of the xiphisternal, and has a similar in- 

 sertion. More direct retractors of 

 the pelvis are the muscle called 

 flexor caudce obturator ius, which 

 arises from the caudal haemapo- 

 physes, and is inserted into the 

 front border of the obturator 

 foramen ; and the flexor cauda> 

 ischiadicus, ib. 52, with a similar 

 origin, but inserted into the ischial 

 symphysis. The pectineus (iliacus 

 interims, Boj.}, figs. 150, 152, 153, 91, arises from the upper surface 

 and outer process of the pubis, and is inserted into the inner tro- 

 chanter of the femur. Its insertion receives also a small fasciculus 

 from the ninth dorsal centrum, and the tenth pleurapophysis, which 

 may represent the psoas. A glutens, figs. 150, 151, 93, arises from 

 the ninth and tenth pleurapophyses, and from the ilium. A second 

 glutaus, figs. 150, 151, 152, 94, arises from the sacral and anterior 

 caudal pleurapophyses. Both are inserted into the outer trochanter, 

 together with a fasciculus, representing an obturator ius, from the 

 inner surface of the obturator fascia, and from the ischial symphysis. 

 The triceps adductor, figs. 152, 153, 97, arises from the inferior sur- 

 face of the pubis, and is inserted into the inner trochanter, crossed 

 by the ischio-pubic ligament. The quadratu$, fig. 152, 98, arises 

 from the tuber ischii, and is inserted into the back interspace of 

 the trochanters. The rectus femoris, fig. 151, 99, arises by a bifid 

 tendon from the upper end of the ilium, and is inserted, with the 

 vastus externus, fig. 150, TOU, vastus internus, fig. 151, 101, crurceus, 

 fig. 152, 102, and sartorius, fig. 153, 106, into the fore-part of the 

 head of the tibia. The semitendinosus, figs. 150, 152, 104, has 

 three origins, one from the back part of the upper end of the 

 ilium and contiguous part of the sacrum, a second from the tuber 

 ischia, a third from the back part of the ischial symphysis ; they 

 join a common tendon which passes behind the knee-joint, and 

 then bifurcates to be inserted into the outer proximal tuberosity 

 of the tibia, and into the gastrocnemius, 1 1 4 b. The semimem- 

 branosus, fig. 153, 105, has two origins, one, 105 , from the first 

 caudal vertebra ; the other, 105 b, from the tuber ischii and ischio- 

 pubic ligament. It is inserted into the upper part of the tibia. 

 The yracilis, fig. 153, 107, arises from the middle of ischiopubic 

 ligament, and is inserted into the upper and outer part of the 

 tibia. The extensor communis dicjitorum, fig. 151, 108, arises from 



