182 SMITHSONIAN CONTKIBUTIONS TO KNOWLEDGE VOL. 35 



form a narrow band around tlie medullary canal. The lacunae and canaliculi 

 are well developed. 

 Type I-III, C. 



FEMUK OF AN ADULT EGYPTIAN. NO. 256478(23), U. S. NAT. MUS. 



Pl. 28, Fig. 370. Syn. Tab. IX 



Antero-posterior diameter of bone, 24 mm. ; lateral, 30 mm. 



Antero-posterior diameter of medullary canal, 10 mm. ; lateral, 10 mm. 



The bone is chalky. 



The medullary canal is full. Medullary index, 16%. 



Structure. — The external circumferential lamellfe surround the bone. Their 

 lacuna are long and narrow and their canaliculi are long and branching. 



The central ring, of well developed Haversian systems, forms nearly the 

 whole thickness of the wall of the bone. The systems are close together, which 

 means that there are little or no inter-Haversian lamellae, and they are generally 

 large and uniform in size and shape. Their lacunae are long and narrow and 

 their canaliculi are long and branching, or the lacunae may be oval and their 

 canaliculi short and bushy. 



The internal circumferential lamella' surround the medullary canal. The 

 ring varies in thickness. 



Type III, C. 



right femur of AN ADULT EGYPTIAN. NO. 2.56478(x), U. S. NAT. MUS. 



Vh. 2S. Fjg. 311. Syn. Tah. IX 



Antero-posterior diameter of bono, 2."I iiiiii.; lateral, 27 iiitn. 



Antero posterior diameter of medullary canal, 12 mm.; latci'al, 11 mm. 



The femur is small. The medullary canal is full. Medullary index, 27%. 



Structure. — The external circumferential lamella' are fragmentary. Be- 

 ginning on the inner side of the posterior ridge and extending around the 

 external surface of the inner lateral wall is a band of lamellae enclosing Ha- 

 versian systems. As the band reaches the mid-lateral wall it is displaced by 

 Haversian systems. In the inner anterior wall concentric systems and lamella' 

 alternate. The remaining portion of the section is composed of Haversian sys- 

 tems somewhat irregular in shape and size. The lacuniB are oval in some places 

 and narrow in others, the oval predominating. The external part of the pos- 

 terior ridge is composed of large, oval lacunae with bushy canaliculi. 



The internal circumferential lamellae are fragmentary. The evidence of the 

 lamellar horseshoe is present to a small extent as a background in the inner 

 wall, while the section is nearly all Haversian systems. 



Type I-III, C. 



