UPPER AND LCAVER LIMBS COMPARED. llo 



Tibia (continued) 



The lower epiphysis appears in the 2nd year. 



The lower epiphysis and shaft unite in the 18th or 19th year. 



The upper epiphysis and shaft unite in the 21st or 22nd year. 



IV. Fibula. 



The nucleus of the shaft appears soon after that of the tibia. 



The lower epiphysis appears in the 2nd year. 



The upper epiphysis appears in the 3rd or 4th year. 



The lower epiphysis and shaft unite in the 21st year or later. 



The upper epiphysis and shaft unite after union of the lower epiphysis. 



V. Patella. 



Ossification begins in the 3rd year, 



VI. Tarsus. 



The nucleus of the os calcis appears in the 6th month. 



The nucleus of the astragalus appears in the 7th month. 



The nucleus of the cuboid bone appears at birth. 



The nucleus of the external cuneiform bone appears in the 1st year. 



The nucleus of the internal cuneiform bone appears in the 3rd year. 



The nucleus of the middle cuneiform bone appears in the 4th year. 



The nucleus of the scaphoid bone appears in the 4th or 5th year. 



The epiphysis of the os calcis appears in the 10th year. 



The epiphysis of the os calcis is united, in the 15th or 16th year. 



VII. Metatarsus. 



The nuclei of the shafts appear in the 8th or 9th week. 



The epiphyses appear in the 3rd to the 8th year. 



The shafts and epiphyses unite from the 18th to the 20th year. 



VIII. Phalanges. 



The nuclei of the shafts appear in the 9th or 10th week. 



The epiphyses appear from the 5th to the 8th year. 



The shafts and epiphyses unite from the 19th to the 21st year. 



COMPARISON OF THE UPPER WITH THE LOWER LIMB. 



The general resemblance which is manifest between the upper and lower limbs is 

 found, on a closer inspection, to result from a community of plan, which can be 

 traced even into certain comparatively minute details, and is not confined to any one 

 system. The details of the correspondence in many points, however, are still un- 

 determined, and even with regard to some parts of the skeleton, variety of opinion still 

 exists. In the hand and foot the correspondence of the bones is very plain. The 

 palmar and plantar aspects being regarded as similar, the great toe corresponds 

 obviously to the thumb ; the four anterior tarsal bones bear a close resemblance to the 

 four inferior carpal bones in the particulars of their metatarsal articulations ; and 

 of the remaining tarsal bones the scaphoid obviously corresponds to the bone of the 

 same name in the hand, the astragalus to the semilunar bone, and the os calcis to 

 the cuneiform and pisiform bones united. The great difference in the appearance of 

 the tarsus from that of the carpus depends principally on the large development 

 of the os calcis and astragalus, by means of which the scaphoid is thrown for- 

 ward and inwards, and the aspect of the tarsus morphologically posterior, that on 

 which the flexor tendons pass to the sole, is turned towards the inner side. If 

 this be the correct comparison of the bones of the hand and foot, with regard to 

 which there cannot be any doubt, it naturally follows that the tibia, lying as it does 

 on the same side of the limb as the great toe, corresponds with the radius : a doctrine 

 which, first laid down by De Blainville and then by Barclay, has been subsequently 

 enunciated by Flourens and Owen. Some anatomists, however, struck by the resem- 

 blance of the patella to the olecranon, in position and in giving attachment to an ex- 

 tensor muscle similar in appearance to the triceps extensor brachii, have taken a dif- 

 ferent view ; thus, according to Vicq D'Azyr, the tibia corresponds with the ulna of 

 the opposite side of the body, while, according to Bourgery, Cruveilhier, and Martins, 

 its upper end corresponds with the ulna and its lower end with the radius of the 



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