218 SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE VOL. 35 



ELEVENTH SECTION 



Antero-posterior diameter of bone, 32 mm. ; lateral, 30 mm. 



Antero-posterior diameter of medullary canal, 26 mm.; lateral, 21 mm. 



Medullary index, 69%. 



Structure of the ninth, tenth, and eleventh sections.— \Yith the exception of 

 the posterior ridges these sections were composed of an external horseshoe- 

 shaped band of lamellae, which was wide in the anterior and very narrow in the 

 lateral wall. The lamellar band was frequently interrupted by Haversian sys- 

 tems, some of which were senile. The central ring was composed of well devel- 

 oped, small and large Haversian systems, some of which were senile. The 

 internal circumferential lamellfe were fragmentary. 



The principal variations in these sections were seen in the appearance of 

 the band of lamelljE and reappearance of the cancellous bone. 



TWELFTH SECTION 



Antero-posterior diameter of bone, 33 mm. ; lateral, 28 mm. 

 Antero-posterior diameter of medullary canal, 20 mm. ; lateral, 19 mm. 

 Medullary index, 126%. 



THIRTEENTH SECTION 



Antero-posterior diameter of bone, 27 mm.; lateral, 36 mm. 

 Cancellous. 



FOURTEENTH SECTION 



Antero-posterior diameter of bone, 28 mm. ; lateral, 44 mm. 

 Cancellous. 



FIFTEENTH SECTION 



Antero-posterior diameter of bone, 35 mm. ; lateral, 70 mm. 



Cancellous. 



Structure of twelfth, thirteenth, fourteenth, and fifteenth sections. — These 

 were composed of Haversian systems and some inter-Haversian lamellae. The 

 band of lamelte was not present. The systems were small and large, and some 

 were senile. The external circumferential lamelte were fragmentary and the 

 internal were cancellous. 



The type was III, C, senile. 



