NO. 3 COMPARATIVE HISTOLOGY OF FEMUR FOOTE 107 



In the posterior wall the lamina* are interrupted by a few Haversian sys- 

 tems well developed. In the inner wall the laminae are more uniformly con- 

 centric. 



Type II. 



RIGHT FEMUR OF TAUROTRAGUS ORYX. ELAND. NO. 27891, AMER. MUS. NAT. HIST. 



Pl. 12, Fig. 310. Syn. Tab. V 



Antero-posterior diameter of bone, 55 mm. ; lateral, 44 mm. 



Antero-posterior diameter of medullary canal, 35 mm. ; lateral, 30 mm. 



The medullary canal is full. Medullary index, 73 %. 



Structure. — The section is composed entirely of laminae with the exception 

 of the posterior ridge. They are short in the anterior wall and of varying 

 lengths in the lateral wall. Their lacunae are generally oval and their canaliculi 

 are straight. The posterior ridge is composed of irregular Haversian systems, 

 separated by bone substance with oval lacunae and bushy canaliculi. 



Type II. 



LEFT FEJVIUR OF CONNOCHyETES TAURINUS ALBOJUBATUS. GNU. NO. 27824, 



AMER. MUS. NAT. HIST. 



Pl. 12, Fig. 211. Stn. Tab. V 



Antero-posterior diameter of bone, 33.5 mm. ; lateral, 30 mm. 



Antero-posterior diameter of medullary canal, 20 mm.; lateral, 17.5 mm. 



The medullary caual is full. Medullary index, 53%. 



Structure. — With the exception of the posterior ridge the section is com- 

 posed of short and long laminae. The laminae are composed of lamellae with oval 

 lacunae and straight canaliculi and are separated and crossed by canals. 



The ridge is composed of fairly well developed Haversian systems, separ- 

 ated by short lamellje with oval lacunae and bushy canaliculi. 



Type II. 



RIGHT FEMUR OF OVIBOS MOSCHATUS WAHDI. MUSK OX. AMER. MUS. NAT. HIST. 



Pl. 12, Fig. 212. Syn. Tab. V 



Antero-posterior diameter of bone, 36 mm. ; lateral, 34 mm. 



Antero-posterior diameter of medullary canal, 30 mm. ; lateral, 28 mm. 



The medullary canal is full. Medullary index, 219%. 



Structure. — The section is composed of laminae with oval lacunae and 

 straight canaliculi, separated by concentric canals. The lamina are short and 

 long, and interrupted here and there by small Haversian systems of the (lb) 

 differentiation: The posterior ridge is composed of small Haversian systems. 



