40 ANTHROPOLOGY. 



rated by interosseous spaces : its jjosteriur border is connected to the tarsus 

 by an irregular transverse line of articulation ; convex forwards, concave 

 backwards. The first or internal of these bones is shortest and thickest ; its 

 anterior end supports the great toe. The second is the longest ; its tarsal 

 end is articulated to the three cuneiform bones. The third is a little shorter 

 than the second ; its base rests on the third cuneiform bone. The fourth 

 is still shorter ; it rests on the cuboid bone, and touches the third cuneiform. 

 The fifth is shortest, excepting the first; it rests on the cuboid bone, with a 

 styloid process externally for the insertion of a muscle. The heads of all 

 the metatarsal bones are round, the bases flat and somewhat square, to 

 articulate with the tarsus; the sides of the bases also are flat, to join one 

 another. 



The toes {pi. 12S,ft(j. 49 "• '"• ") are five in number : the first or great toe has 

 only two phalanges ; all the rest have three, making fourteen phalanges in all. 

 The first phalanges are longest; the second are very short; the third, also, 

 are very small. At the base of the first phalanx of the great toe there are 

 usually two sesamoid bones, over which the small muscles of this toe glide ; 

 the sesamoid bones may also occur in some of the other toes. 



B. Articulations and Ligaments of the Inferior Extremities. 



1. Articulation between the Pelvis and the Spine. The last lum- 

 bar vertebra is joined to the sacrum in the same manner as the other verte- 

 brae are joined to each other, by an intervertebral, anterior and posterior, 

 yellow, supra, and interspinous synovial membranes, and capsular ligaments. 

 The connexion is also strengthened by tlie lumbosacral ligament, a short, 

 thick, fibrous band, extending from the transverse process of the last lumbar 

 vertebra to the posterior part of the base of the sacrum. 



The two last lumbar vertebrie are connected with the ilium by the ilio- 

 lumbar ligament {pi. 125, figs. 4\ 5 '•■*). Tliis is sometimes divided into 

 two ; it arises from the transverse processes of the fifth and fourth lumbar 

 vertebree, and from the back jiart of the sacrum, and is inserted into the 

 posterior superior spine of the ilium, and into its crest. 



The articulations of the pelvic bones with each other are the sacro-coccy- 

 geal, the sacro-iliac, the sacro-sciatic, and the pubic. There are no perfect 

 or true joints between the pelvic bones. 



The sacrum and coccyx are joined by a thin anterior, and a thick 

 posterior sacro-coccygean ligament {figs. 4^, 5"), as also by a thin inter- 

 vertebral fibro-cartilage. The articulation usually allows of more motion in 

 the female than the male. 



The sacro-iliac articulation is secured by an anterior and posterior liga- 

 ment. The anterior sacro-iliac ligament {fig. 4") is thin, and consists of 

 fibres passing transversely from one bone to another ; the posterior {fig. 5 ^) 

 consists of fasciculi passing from the rough surfixce of the sacrum to that of 

 the ilium, and to its posterior superior spine. The sacro-iliac .symphysis 

 connects the articular surface of these bones, which in the aged are some- 

 times anchylosed. 



The sacrum and ischium, though not in contact, are connected by very 

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