56 



PLATE XXVITL 



MUSCLES 



A Gluteus medius. 



B Gluteus minimus. 



C Pyriformis. 



D Obturator interims. 1 



E Gemellus inferior. 



F Quadratus femoris. 



6 Adductor magnus. 



H Gluteus maximus. 



I Vastus externus. 



K Great sacro-sciatic ligament cut and 



turned down. 



L Biceps and semitendinosus, origin from 



tuber ischii. 



M Lesser sacro-sciatio ligament and 



coccygeus. 

 N Spine of ischium. 

 Levator ani. 

 P External sphincter. 

 R Vertebral aponeurosis. 

 8 Tendon of obturator externus. 

 V Placed over the sacro coccygeal joint. 

 W Section of sacrum. 

 X Section of ilium. 

 Y Tuber ischii. 

 Z Great trochanter. 



VESSELS 



a Gluteal artery. 



b Superficial division of the gluteal. 



c Deep division of the gluteal. 



d Sciatic artery. 



e Internal pudic. 



/ Anastomotic branch of internal circum- 

 flex to the digital fossa. 



NERVES 



1 Lumbo-sacral cord. 



2 First sacral. 



8 Second sacral. 



4 Third sacral. 



5 Foufth sacral. 



6 Fifth sacral. 



7 Coccygeal. 



8 Superior gluteal. 



9 Branch from second to pyriforinis. 



10 Inferior gluteal. 



11 Great sciatic. 



12 Small sciatic. 



18 Inferior pudendal. 



14 Recurrent gluteal branches of small 

 sciatic. 



15 Nerve to quadratus femoris, inferior 



gemellus, and hip-joint. 



16 Nerve to obturator internus and 



superior gemellus. 



17 Internal pudic. 



18 Perforating cutaneous nerve (n. per- 



forans cutaneus). 

 19) Visceral branches of third and fourth 



20 j sacral. 



21 Nerve to coccygeus. 



22 Nerve to sphincter. 



23 Nerve to levator ani. 



24 Nerve formed by the junction of fourth 



and fifth sacral and coccygeal, dis- 

 tributed to skin (ano-caudal). 



In some cases it will be found that the small sacro-sciatic ligament is entirely or 

 partly replaced by fibres of the coccygeus muscle, of which it appears to be a fibrous 

 retrogression ; in the armadillo this is again replaced by bone. 



1 The muscle substance was very thin in this body, and there was complete absence of the gemellus 

 superior. 



