780 MAMMALIAN ANATOMY 



tarsal with the long proximal tuberosity. When held with the base 

 uppermost and the plantar side toward the student, the tuberosity is on 

 the side to which the bone belongs. 



Muscular Attachments. The base of the fifth metatarsal affords 

 insertion to the peroneus brevis and the abductor ossis metatarsi, and 

 origin to the extensor brevis digitorum and the fourth plantar inter- 

 osseous. The opponens minimi digiti is inserted along the tibial side 

 of the shaft, on the plantar aspect. 



THE PHALANGES. 



Every one of the four digits, or toes, which compose the distal part 

 of the foot consists of three phalanges, constructed on the same plan 

 as the phalanges of the fingers and closely resembling them. 



THE PROXIMAL PHALANGES. 



Every Proximal Phalanx has its proximal end or base excavated 

 to articulate with the rounded head of its metatarsal, and the distal end 

 or head formed of a trochlea or pulley, which is convex from the 

 dorsal to the plantar side, concave transversely, and articulates with 

 the proximal end of the middle phalanx. 



The third proximal phalanx is very little larger than the fourth, 

 and both are longer and stouter than the second, which in turn is 

 longer and stouter than the fifth. The third and fourth are bilater- 

 ally symmetrical, but the second and especially the fifth have the 

 median side more strongly concave than the opposite side. 



The proximal phalanges of the toes are shorter and stouter in pro- 

 portion to the length of the foot than the corresponding phalanges of 

 the fingers are in proportion to the length of the hand. 



THE MIDDLE PHALANGES. 



The Middle Phalanx of a toe is recognized by its concave proximal 

 surface, with its overhanging dorsal projection, by the concavity on 

 the fibular side of the shaft, and by the transversely cylindrical head. 

 The middle phalanges decrease in size from the third to the fifth in 

 the same order as the metatarsals. As compared with the middle 

 phalanges of the fingers, they are shorter and stouter. 



THE DISTAL PHALANGES. 



The Distal Phalanx bears the large, triangular, curved claw-plate 

 on its dorsal surface. It is in all respects like the distal phalanx of 



