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SOLIPEDA. 



tata, these six muscles exist and are disposed 

 pretty nearly as in tlie human race ; but in the 

 Pachydermata and Ruminantia there is but 

 one flexor carpi raclialis. In all the above 

 multidigitate animals, the muscles derived 

 from the external condyle, and its vicinity by 

 their co-operation, approximate the back of 

 the hand towards the forearm, or, in other 

 words, are extensors of the fore-foot ; while 

 those derived from the internal conclyle have 

 a contrary effect, and act as flexors of the 

 hand. Should the flexor and extensor of the 

 same side of the limb act together, the hand 

 will be bent laterally in the corresponding 

 direction. 



In the Solipeda, where the movements of 

 the wrist are strictly limited to those of 

 flexion and extension, the disposition of these 

 muscles is considerably modified. 



The extensor carpi radialis is here single, 

 arising from the anterior part of the external 

 condyle of the humerus, and from the ex- 

 ternal surface of that bone for a consider- 

 able distance : it forms a strong fleshy belly, 

 terminating in a powerful tendon, which runs 

 to be inserted into the base of the anterior 

 surface of the metacarpal or cannon bone. 

 Tin's muscle, called by Bourgelat the " extcn- 

 sejtr droif anterieitr da canon," seems, from the 

 extent of its origin, to represent the long su- 

 pinator and the two radial extensors of the 

 wrist combined, and all three made to co- 

 operate in the extension of the wrist. 



The flexor carpi radialis {epitrochlo-meti- 

 carpien) arises from the external condyle of 

 the humerus, and is inserted into the posterior 

 surface of the base of the cannon bone, form- 

 ing the antagonist to the preceding muscle : 

 this is the "flechisseur interne du canon " of 

 Bourgelat. 



The flexor carpi ii/nnris (epitrocltlo-crirpieii) 

 arises from the posterior part of the external 

 protuberance of the os humeri, and also by a 

 distinct head from the protuberance situated 

 above the internal condyle ; its tendon is in- 

 serted into the representative of the pisiform 

 bone and also into the root of the rudi- 

 mentary metacarpal bone beneath it : this is 

 the " flechisscur oblique du canon " of Bour- 

 gelat. 



The extensor carpi uhiaris ( ci/bito-sus-me- 

 tacarpien') arises from the posterior part of 

 the external condyle of the humerus, and 

 is inserted, like the preceding, into the os 

 pisiforme, whence it is prolonged beneath 

 the carpus, so as to perform the office of 

 a flexor of the wrist (_" Jlcc/iisseur externe " 

 Bourgelat.) 



The palmarls fangus does not exist in the 

 Solipeda ; nor is it tbund in the Pachydermata 

 and Ruminantia, being in these orders of qua- 

 drupeds apparently combined with the flexor 

 suhiimis digitorum, as is likewise the case 

 with this muscle in the bear, the badger, and 

 the clog ; in all other unguiculate quadrupeds 

 it is disposed as in the human subject. 



Muscles of the hand. The extensor com- 

 munis digi for/in/ (epicondylo-sus-phalangettien 

 commun\ This muscle in the horse is called 



by Bourgelat " / 'extcnseur anterieur du pied, " 

 and by Lafosse, " I ' extenseur du pied :" it arises 

 from the external condyle of the humerus and 

 from the contiguous fasciae, also from the upper 

 and lateral part of the radius; its fleshy belly 

 is strong, and terminates in a single tendon, 

 which runs over the foot to be inserted into 

 the last phalanx or coffin-bone, having pre- 

 viously given off a slip to join the tendon of 

 the extensor minimi d;giti. 



Fi. 502. 



Myology of the Horse. (After Stul/bs.) 



Head. a, Orbicular muscle of the mouth ; g, ele- 

 vator of the chin ; 5, arteria angularis ; 6, arteria 

 temporalis. 



Neck. /, Obliquus capitis inferior ; 7, ligamen- 

 tum michse. 



Trunk. m, Transversalis abclominis ; t, sphincter 

 anL 



Left anterior Extremity. u; Insertion of bra- 

 chialis antieus ; d, flexor pvofundus digiti ; p, flexor 

 carpi radialis; it, ligaments of the" carpus; I, m, 

 tendon of the flexor sublimis perforatus. 



Right anterior Extremity. /, in, Tendon of the 

 flexor sublimis; z, insertion of flexor profimdus into 

 the coffin bone ; r, flexor brevis digiti pedis. 



Lift posterior Extremity. p, adductor magnus 

 fnnnris ; 7, vastus interims ; u, gracilis ; 13, 15, plan- 

 tans ; 28, flexor longus digiti pedis ; 1(>, external 

 malleolus; 17, Internal malleolus; 18, division of 

 the tendon of plantaris, to allow the tendon of the 

 flexor profimdus to proceed to its insertion at 31, 

 into the coffin bone; 11, flexor brevis digiti pedis; 

 36, obturator artery ; 37, nerves to the tibialis an- 

 ticiis. 



li'njht jitmtcrinr Extremity. c, Trail versalis penis ; 



