NO. 3 COMPARATIVE HISTOLOGY OF FEMUR FOOTE 167 



XIII. MAN— YELLOW-BROWN RACE 



General Character of the Femur 



Witli one e.xception the femora of tlie yellow-brown race are pre-Colum- 

 bian. The series includes infantile, adolescent, and adult bones from the 

 Pueblo, Chicama, and Pachacamac Indians. 



The general shape of these femora is nearer circular than it is in the 

 black or white races. The medullary canals were filled with marrow and 

 cancellous bone. The medullary surfaces are irre^lar and corrugated. The 

 medullary index varies from 19% to 100%, with an average of 43.8%. 



Nearly all of the femora are composed of type combinations. The propor- 

 tion of first type units is larger than it is in other races. 



Detailed Examination 



kleiht femur of a pueblo indian chili), one year old. no. :258675(z), 



u. s. nat. mus. 



Pl. 25, Fig. 341. Syn. Tab. IX 



Antero-posterior diameter of bone, 8 mm. ; lateral, 7.5 mm. 



Antero-posterior diameter of medullary canal, 4.5 mm. ; lateral, 4 mm. 



The medullary canal is full. Medullary index, 43%. 



Structure. — Around the external portion of the section is a horseshoe- 

 shaj)ed band of crude Haversian systems in various stages of differentiation. 

 Some are round, some elongated, and many are irregulai' in shape. Their 

 Haversian canals of the (lb) ditferentiation are relatively large and surrounded 

 by lamell!P witli oval lacuna" and ratlici- infre(|U('nt cauali<"uli. The toe of tlie 

 shoe is best developed and widest. 



Underneath the Haversian band is a wider liorscshdc band, forming the 

 remainder of the section, and composed of lamina^ between which are concen- 

 tric canals. In the anterioi- and outer wall the lamina' are assuming the shape 

 of very much elongated Haversian systems. The posterioi' ridge is composed 

 of crude, elongated Haversian systems, which extend from tlie external to the 

 medullary surface and at right angles to the laminae of the lateral wall. The 

 systems have wide Haversian canals, surrounded by lamella; with oval lacunaj 

 and bushy canaliculi. A large vascular canal is seen in the inner posterior 

 wall. 



The internal circumferential lamella; surround the medullary canal in the 



form of cancellous bone. 

 Type II-III, lb. 



12 



