NO. 3 



COMPARATIVE HISTOLOGY OF FEMUR FOOTE 



39 



RIGHT FEMUR OF HYLA EVITTATA. NO. E 55 17, U. S. NAT. MUS. 



Pl. 2, Pig. 10. Syn. Tab. I 



Antero-posterior diameter of bone, 0.5 mm. ; lateral, 0.2 mm. 

 Antero-posterior diameter of medullary canal, 0.4 mm.; lateral, 0.1 mm. 

 The medullary canal is full. Medullary index, 104%. 



Structure. — The section is composed of concentric lamellae with oval lacuna j 

 and long canaliculi, divided into wide external and narrow internal concentric 

 rings which surround the medullary canal, a twofold division. 



Type I. 



RIGHT FEMUR OF HYLA CINEBEA. NO. 13095, U. S. NAT. MUS. 



Pl. 2, Fig. 11. Syn. Tab. I 



Antero-posterior diameter of bone, 1.5 mm. ; lateral, 1 mm. 

 Antero-posterior diameter of medullary canal, 0.5 mm. ; lateral, 0.4 mm. 

 The medullary canal is full. Medullary index, 14%. 



Structure. — The section has a long posterior process, the central position 

 of which, from the medullary canal to the tip, is occupied by bone substance 

 with a few oval lacunas and branching canaliculi. The body of the section is 

 composed of lamella? with oval lacunae and straight canaliculi. A narrow ring 

 of internal circumferential lamella? surrounds the medullary canal. The section 

 shows a twofold division. 



Type I. 



RIGHT FEMUR OF HYLA REGILLA. NO. E 62 39, U. S. NAT. MUS. 



Pl. 2, Pig. 12. Syn. Tab. I 



Antero-posterior diameter of bone, 1 mm. ; lateral, 0.9 mm. 

 Antero-posterior diameter of medullary canal, 0.5 mm. ; lateral, 0.5 mm. 

 The medullary canal is full. Medullary index, 38%. 



Structure. — The section is composed of lamella? with oval lacuna? and long 

 canaliculi, divided into wide external and narrow internal rings. The internal 

 ring forms the internal circumferential lamella?. Twofold division. 



Type I. 



RIGHT FEMUR OF HYLA SQUIRELLA. NO. E 51 2, U. S. NAT. MUS. 



Pl. 2, Fig. 13. Syn. Tab. I 



Antero-posterior diameter of bone, 0.8 mm,; lateral, 0.5 mm. 

 Antero-posterior diameter of medullary canal, 0.5 mm. ; lateral, 0.4 mm. 

 The medullary canal is full. Medullary index, 92%. ] 



