552 



THE ARTERIES. 



larger than the preceding, this vessel (Fig. 278, 3) may be considered as a 

 continuation of the primitive pedal artery. It is lodged at first in the 

 fissure situated outside the middle metatarsal bone, in front of the external 

 metatarsal bone, and afterwards passes between these two bones, above the 

 tubercle terminating the latter, reaching the posterior face of the first, 

 between the two inferior branches of the suspensory 

 Fig. 278. ligament, above the sesamoid groove, where the vessel 



bifurcates to form the collateral arteries of the digit. 



The collateral artery of the cannon receives, a short 

 distance above this terminal bifurcation, the internal 

 plantar interosseous artery. 



On its course it gives off: 1, Numerous anterior 

 ramuscules for the cellular tissue, tendons, ligaments, 

 and the skin on the anterior face of the metatarsus and 

 fetlock ; 2, Some thin posterior divisions, one of which 

 ascends within the external metatarsal bone to anastomose 

 with the external plantar interosseous artery, after fur- 

 nishing several ligamentous, tendinous, and cutaneous 

 ramuscules in the posterior metatarsal region. 



DIGITAL ARTERIES, OR COLLATERAL ARTERIES OP THE 

 DIGIT (Figs. 277, 25; 278, 4; 283, 11). Remarkable 

 for their volume, these arteries carry blood to the 

 keratogenous apparatus enveloping the ungual phalanx, 

 and from this destination derive such importance that 

 they deserve a detailed study. 



Origin. The digital arteries succeed the terminal 

 extremity of the collateral of the cannon, and separate 

 from one another in forming an acute angle below the 

 sesamoid venous arch, above the fetlock joint, between 

 the two branches of the suspensory ligament, behind the 

 inferior extremity of the principal metatarsal bone, and 

 in front of the flexor tendons of the phalanges. 



Course and Relations. These vessels descend, one to 

 the right, the other to the left, from the lateral parts of 

 the metacarpo-phalangeal (and metatarso-phalangeal) 

 articulation to the internal face of the basilar process, 

 PRINCIPAL ARTERIES w h ere they bifurcate to form the plantar and preplantar 



AND VEINS OF THE 7 . 



POSTERIOR FOOT ungueol arteries. 



1 Anterior tibial ar- " In the whole of this COUrse ' {t ( the dl 9 lial arien j) 



tery ; 1', Pedal ar- follows the track of the flexor tendons, on whose margin 



tery ; 2, Perfora- it rests, and where it is maintained by loose connective 



ting pedal artery ; tissue. Behind, it is flanked by the plantar nerve, which 

 3, Metatarso-pedal, 



or collateral artery 



of the cannon; 4, 



Digital artery ; 5, It would have been better to have allowed it to retain the name 



Anterior tibial ar- given to it by Girard the lateral artery of the cannon. This is 



tery ; 6, Posterior not the only instance in which the attempts of Rigot to conform the 



root of the internal nomenclature of the arteries to that of anthropotomists has proved 



saphena vein ; 7, unfortunate, as he has not always succeeded in finding in the 



Origin of the ex- Horse the real representatives of arteries in Man. The aim of 



ternal saphena vein; this work does not allow us to discuss the vicious determinations 



8, 9, 10, Metatarsal and denominations of Rigot every time we meet them. "We 



veins; 11, Digital are content to c'hange them, purely and simply, leaving to the 



veia ; 12, Venous judgment of the reader, should this matter interest him, the task 



plexus of the foot, of deciding if we are right. 



