776 



TEE NEBVKS. 



4 



The longest and thickest of these goes to the quadratus femoris. That 

 passing to the obturator internus re-enters the pelvic-cavity by the small 

 ischiatic notch, and ascends to the vicinity of the ilio-sacral articulation. 



3. Branch to the Isohio-tibial 



^'S- 357. Qjj POSTEKIOK CrTJRAL MuSCLES. — 



This branch is thick and short ; it 

 arises from the bend formed by the 

 great femoro-popliteal nerve at thi 

 gemini muscles, and soon divides int 

 several ramifications vphich are dis- 

 tributed to the short portion of the 

 triceps cruris, the middle and inferior 

 parts of the semitendinosus, and into 

 the semimembranosus. Some of the 

 filaments destined to the latter muscle 

 pass between it and the great adductor 

 of the thigh, in v^hich they partly 

 terminate (Fig. 356, 12). 



4. External Saphenous Nerve. 

 — This branch commences at from 2 

 to 6 inches from the point where the 

 great sciatic nerve dips between the 

 gastrocnemii muscles. It is placed 

 on the external gastrocnemius, and 

 descends underneath the special apo- 

 neurotic layer covering that muscle, 

 to the origin of the tendon of the 

 hock. It then receives its accessory 

 nerve — the reinforcing filament which 

 comes from the cutaneous branch of 

 the small femoro-popliteal nerve, and 

 is prolonged beneath the tibial apo- 

 neurosis into the channel of the hook, 

 accompanying the external saphenous 

 vein, and following the external 

 border of the fibrous band that goes 

 to strengthen the tendo-Achillis. In 

 this way, it occupies the same situa- 

 tion outside the hock that the great 

 sciatic does on the inner side. It 

 afterwards passes over the tarsal 



1, 2, Great sciatic nerve ; 3, External saphena region, and is expended On the OUtside 



trr^fbifl"e\''?MtcX:^tatt; Of the metatarsus in several filaments, 



nerve; 7, Origin of the peroneal-cutaneous some ot Which descend to the outer 



branch ; 8, Accessory branch of the external aspect of the digit (Figs. 356, 13; 



saphenous nerve ; 9, External plantar nerve 357 g\ 



Til^rv^and velr' ^^'"^ ™^"' ^^' '^'^"'' 'S- ^ASCICTJLI TO THE POSTERIOR 



Tibial Muscles. — This fasciculus is 

 composed of numerous branches, which are detached together from the 

 sciatic nerve on its passage between the gastrocnemii muscles, in the form 

 of a thick short trunk. The muscles of the superficial layer — the gastro- 

 cnemii, perforatus. and the thin fleshy band, improperly designated the small 

 plantaris by Veterinarians — receive ramuscules which are remarkable for their 



EXTERNAL NERVES OP THE POSTERIOR 

 LIMB. 



