DORSALIS PEDIS 601 



branches with the coHateral (lif!;ital hranclies of the digital arteries, which also run 

 along the sides of the toes, but nearer the j)lantar surface. At the end of the toes 

 they anastomose with each other around the (juick of the nail. 



(3) The dorsalis hallucis — or first dorsal interosseous artery, as it is some- 

 times called — is the aiii)ar(iit continuation of the dorsalis ])edis. Like the other 

 dorsal interosseous arteries, it passes forwards, in the centre of the first interosseous 

 space, on the first dorsal interosseous muscle. At the cleft of the toes it divides 

 into two dorsal digital branches — the one for the supply of the outer side of the 

 great toe, the other for the inner side of the second toe. Before its bifurcation 

 the dorsalis hallucis gives off a small branch, which runs inwards, under the 

 extensor longus hallucis, for the sujiply of the inner side of the great toe; but this 

 branch is sometimes absent. At the front of the s})ace, immediately before its 

 bifurcation, the dorsalis hallucis communicates with the fifth plantar digital artery, 

 or i)rinceps hallucis, through an anterior perforating artery (fig. 381). 



(4) The communicating — first interosseous perforating, or plantar digital 

 artery, as it is variously called — comes ofif from the dorsalis pedis with the dorsalis 

 hallucis (into which arteries indeed the dorsalis pedis may be said to divide). At 

 the back of the first interosseous space it dips into the sole between the two heads 

 of the first dorsal interosseous muscle, and communicates with the termination of 

 the external plantar artery, completing the plantar arch, in a manner similar to 

 that in which the radial artery, passing through the first dorsal interosseous muscle 

 in the hand, completes by inosculating with the ulnar the deep palmar arch. At 

 the spot wliere it joins the external plantar it gives off the fifth plantar digital 

 artery, or princeps hallucis, which runs forAvards in the centre of the first inter- 

 osseous space to the cleft between the first and second toe, where it divides into 

 collateral Ijranches for the adjacent side of each. Before bifurcating, it supplies a 

 branch to the inner side of the great toe, and receives the anterior connnunicating 

 arterv from the dorsalis hallucis. 



