122 The Alligator and Its Allies 



II. This is a more anterior and inner muscle, 

 small in size, which has a fleshy origin from the 

 bodies and ribs (transverse processes) of the second 

 sacral and first caudal vertebrce at a distance from 

 the posteromedian border of the ischium. It 

 extends caudad, lying near the hinder part of the 

 pubi-ischio-femoralis externus, and is inserted 

 on the trochanter. 



Flexor Tibialis Externus (Plate III., Figs, i, 2, 

 3, fl. tb. ext. or f. t. ext., Plate IV., Fig. 4, fl. tb. 

 ext., Plate V., Figs, i and 3, fl. tb. ext. and f. t. 

 ext.) (Triceps flexor cruris partim. Biceps). A 

 strong, spindle-shaped muscle that arises, together 

 with the ilio-fibularis, by a short tendon, from the 

 side of the portio dorsalis of the ilium, and in 

 the neighborhood of the bend of the knee is split 

 into two tendons, of which the short one is inserted 

 on the fibular side of the neck of the tibia, while 

 the other, running along near the caput femoris of 

 the gastrocnemius muscle, unites with the tendon 

 of the caput tibiae of the gastrocnemius muscle 

 just beyond the ankle joint. 



Flexor Tibialis Internus (Plate III., Figs, i, 2, 3, 

 fl. tb. int., orf. t. int., Plate IV., Fig. 4, fl. tb. int., 

 Plate v., Fig. i, fl. tb. int.) (Demi-nerveux + 

 Demi-membraneux, Triceps flexor cruris partim, 

 Gracilis, Adductor flexor tibialis. Semimembrano- 

 sus, Semitendinosus + Gracilis partim. Gracilis -f- 

 Scmimembranosus -\- Semitendinosus). A three- 

 headed muscle whose heads arise separately and 



