NO. o COMPARATIVE HISTOLOGY OF FEMUH FOOTE 89 



RIGHT FEMUR OF PlEliOPUS. (JAVA.) No. 1l'()1(), T. S. NAT. MIS. 



Pl. S. Fig. 164. Syx. Tat,. IV 



Aiitero-posterior diameter of bone, 3 mm.; lateral, •'!.') mm. 



Antero-posterior diameter of medullary canal, 2.5 mm.; lateral, - mm. 



The mednllary canal is full. Medullary index, 91'/ . 



8tnicture.—The section is composed of concentric lamella' with oval and 

 long lacunae and straiglit canaliculi, interrupted by many very crude Haversian 

 systems of the (la) differentiation. 



Type I-III, la. 



RIGHT FEMUR OF PTEROPUS LEPICOS. XO. ll'J-i04, U. S. NAT. MUS. 



Pl. 8, Fig. 16.5. Syn. Tab. IV 



Antero-posterior diameter of bone, 2.5 mm.; lateral, 2 mm. 



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



The medullary canal is full. Medullary index, 45%. 



Structure. — The section is composed of concentric lamelhB with oval and 

 long lacunse and straight canaliculi crossed by numerous radiating canals. Here 

 and there a few very crude Haversian systems of the (la) differentiation are 

 seen. The bone is uniform. 



Type I-III, la. 



right femur of PTEROPUS. (tONG.\TABU.) NO. 173884, U. S. NAT. MUS. 



Pl. 8, Fig. 166. Syn. Tab. IV 



Antero-posterior diameter of bone, 3 mm. ; lateral, 3 mm. 



Antero-posterior diameter of medullary canal, 1.5 mm.; lateral, 1.5 mm. 



The medullary canal is full. Medullary index, 33%. 



Structure. — The section is composed of concentric lamelhp with oval lacunae 

 and straight canaliculi, partially separated by undeveloped Haversian systems 

 of the (la) differentiation into two laminte. The systems occupy a central 

 concentric position. The bone has a twofold division. 



Type I-III, la. 



RIGHT FEMUR OF PTEROPUS POLIOCEPHALUS. X^ . S. N.AT. MUS. 



Pl. 1), Fig. 167. Syx. Tab. IV 



Antero-posterior diameter of bone, 3.5 mm.; lateral, 3.5 nun. 

 Antero-posterior diameter of medullary canal, 2 mm. ; lateral, 2 mm. 

 The medullary canal is full. Medullary index, 49%. 



Stnicturc. — The section lias the tlii'ee concentric divisions, external, central, 

 and inlcrnal. Tlie ]a<'un;c arc o\al and tlic canalicnli arc straiiiiil. In tlie i-en 



