18U SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE VOL. 35 



The hone helongs to tlie same series as tlie foregoini"-. 



The medullary canal is full. Medullary index, 44%. 



Sfnictiire. — The section is composed of wide extei'nal and internal lainelUc 

 with a central ring of Haversian systems. Tlie enclosing horseshoe-shaped 

 hand of lamelte is clearly marked. It is fairly uniform in width, and inter- 

 rupted by crude Haversian systems of the (la) differentiation. Around the 

 medullary canal is a wide ring of lamellae of varying widths. It is widest in 

 the inner wall and interrupted by a few incomplete Haversian systems. Be- 

 tween these two bands of lamellae is a narrow middle ring of Haversian sys- 

 tems and inter-Haversian lamellae. The lacuna? are oval and long and their 

 canaliculi are long. 



Type I-III, la, C. 



RIGHT FEMUR OF AN ADULT EGYPTIAN. NO. 1256481(d), U. S. NAT. MUS. 



Pl. 28. Fig. 3G7. Syn. Tab. IX 



Antero-posterior diameter of bone, 18.5 mm.; lateral, 17.5 mm. 



Antero-posterior diameter of medullary canal, 9 nun. ; lateral, 8 mm. 



Tlie medullary canal is full. Medullary index, 28%. 



Structure. — The bone is surrounded by a lamellar ring, within which are a 

 few Haversian systems of the (la) and (C) differentiations. The ring is sep- 

 arated by concentric canals into lamina>. 



The medullary canal is surrouiuled by a wide band of lamella} with long 

 lacunae and straight canaliculi, which in the inner wall rather abruptly widens 

 into a semicircular area of lamina^ occupying nearly the wliole thickness of tlie 

 wall, "^riic huniiia' arc iiiteiTiiptcd li.\' nuincrous MaN'crsiaii systems of the (la) 

 differentiation. Between these two liaiids is an irregularly shaped central ring 

 of Haversian syslenis and iulei' IIa\ crsian lamella'. 'I'lic lacuna- are long and 

 narrow and their canaliculi are long. 



Type I-II-III, la, C. 



LKFI' 1'KMIM; OI'" AN ADULT EGYI'TIAN. NO. 125648 1 ( M ) , V. S. N.AT. MUS. 



Pl. 28. Fig. 3(58. Syn\ Tah. IX 



Anteroposterior diameter of bone, 18 mm.; lateral, 16 mm. 



Antero-posterior diameter of medullary canal, 8 mm.; lateral, 7 mm. 



The medullary canal is full. Medullary index, 24%. 



The bone is very hard and brittle instead of chalky like the other femora 

 described. It is small and nearly round. 



Structure. — The posterior ridge, which is not very prominent, is composed 

 of well developed Haversian systems. 



