THE FOOT 



253 



The second phalanx (phalanx secundd) is remarkably small and short, but 

 rather broader than the first phalanx. 



The ungual or distal phalanx (phalanx tertia) in form resembles the bone of the 

 corresponding finger, but is smaller, flattened from above downward, presenting 

 a broad base for articulation with the second phalanx, and an expanded extremity 

 for the support of the nail and end of the toe. 



ysis. 



Appears 10th year ; 

 unites after puberty. 



Tarsus. 



One centre for each bone, 

 except os calcis. 



Appears 3d year. 

 Unite 18th-20 year. 



Appears 7th week. 



One for proximal 

 extremity. 



Metatarsus. 

 Two centres for each bone : 

 One for shaft, 

 One for digital extremity 

 except 1st. 



Appears 9th week.~~ 



Unite 18th-20th year. 

 Appears 5th-8th year. 



Appears 4th year. 

 Unite 17-18th year, j B 

 Phalanges. Appears 2nd- 4th month. 

 Two centres for each bone : 

 One for shaft, 



Appears 6th-7th year. 



Unite 17th-18th year. \ 



Appears 2nd~4th month. 

 Appears 6th year. 

 J'nite 17th-18th year. -ft 

 Appears 10th week. 



FIG. 206. Plan of the development of the foot. 



Articulation. The first row, with the metatarsal bones behind and second phalanges in 

 front; the second row of the four outer toes, with the first and third phalanges; of the great toe, 

 with the first phalanx; the third row of the four outer toes, with the second phalanges. 



Attachment of Muscles. To the first phalanges: Great toe, five muscles innermost tendon 

 of Extensor brevis digitorum, Abductor hallucis, Adductor obliquus hallucis, Flexor brevis 

 hallucis, Adductor transversus hallucis. Second toe, three muscles First and Second dorsal 

 interosseous and First lumbrical. Third toe, three muscles Third dorsal and First plantar inter- 

 osseous and Second lumbrical. Fourth toe, three muscles Fourth dorsal and Second plantar 

 interosseous and Third lumbrical. Fifth toe, four muscles Flexor brevis minimi digiti, Abduc- 

 tor minimi digiti, and Third plantar interosseous, and Fourth lumbrical. Second phalanges: 

 Great toe Extensor longus hullucis, Flexor longus hallucis. Other toes Flexor brevis digitorum, 

 one slip of the common tendon of the Extensor longus and brevis digitorum. 1 Third phalanges: 

 Two slips from the common tendon of the Extensor longus and Extensor brevis digitorum, and 

 the Flexor longus digitorum. 



1 Except the second phalanx of the fifth toe, which receives no slip from the Extensor brevis digitorum. 



