258 



THE SKELETON. 



Interosseous. Third toe: Third Dorsal and First Plantar Interosseous. Fourth 

 toe : Fourth Dorsal and Second Plantar Interosseous. Fifth toe: Flexor Brevis 

 Minimi Digiti, Abductor Minimi Digiti, and Third Plantar Interosseous. Second 

 phalanges, great toe: Extensor Longus Pollicis, Flexor Longus Pollicis. Other 

 toes : Flexor Brevis Digitorum, one slip from the Extensor Brevis Digitorum 

 (except in the little toe), and Extensor Longus Digitorum. Third phalanges . 

 two slips from the common tendon of the Extensor Longus and Extensor 

 Brevis Digitorum, and the Flexor Longus Digitorum. 



DEVELOPMENT OF THE FOOT. (Fig. 182.) 



The Tarsal Bones are each developed by a single centre, excepting the os 

 calcis, which has an epiphysis for its posterior extremity. The centres make 

 their appearance in the following order : in the os calcis, at the sixth month 



Fig. 182. Plan of the Development of the Foot. 



Tarsuy 



Centre for each lone 

 Os CaZcit 



unites after puterty 



Metatarsus 



2 Centres for each lione 

 1 for Shaft 

 1 far Digital Extremity 



earcrvt iff 



^Centres far each &on0 

 IforShaft 



Appears 6$yf 

 Unite. 18-2.0$ y.". 



of foetal life; in the astragalus, about the seventh month; in the cuboid, at the 

 ninth month ; external cuneiform, during the first year ; internal cuneiform in 

 the third year; middle cuneiform and scaphoid in the fourth year. The 

 epiphysis for the posterior tuberosity of the os calcis appears at the tenth year, 

 and unites with the rest of the bone soon after puberty. 



The Metatarsal Bones are each developed by two centres ; one for the shaft, 

 and one for the digital extremity, in the four outer metatarsal ; one for the shaft, 



