88 SMITHSONIAN COSTBIBUTIOSS TO KNOWLEDGE VOL. oO 



SlrKftiire. — Tlie section is eonii)Ose(l of laiuolhr with oval lacunae and 

 strai.niit caiiiilicnli indistinctly separated into three concentric ring's. Incom- 

 plete thi-eefohl division. 



TjT^e I. 



RIGHT FEMUK OK PTEROPCS MOLOSSINUS (l.^KGE). f. S. NAT. MUS. 



Pl. S. Fig. Kil. Syx. Tab. IY 



Antero-posterior diameter of bone, 3 mm.; lateral, 3.5 nnn. 



Autero-posterior diameter of mednllary canal, 2.5 mm.; lateral, L'.o mm. 



The medullary canal is full. Mednllary index, 147%. 



Stnirhirc. — The section is composed of lamellae with long, narrow lacume 

 and straight canaliculi enclosing the medullary canal. The lamellae are divided 

 into two rings, a narrow external and wide internal. In the inner wall the 

 lamelte are interrupted by a few canals of the (la) differentiation. The femur 

 shows a little advancement. Twofold division. 



Type I-III, la. 



lUGHT I'EMUli OF I'TEHOPUS ALDABKENSIS. NO. 20989, V. S. NAT. MUS. 



Pl. 8. Fig. H\2. 8yx. Tais. IV 



Antero iKtstcrior diameter of bone, 2 nnn.; lateral, 2.5 mm. 



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



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



Sfrucfiirc. — The section is composed of concentric lamella> with oval and 

 long lacuiuv and straight canaliculi interrupted 1»y a few crude, undexcloped 11a 

 versian systems of the (la) differentiation. 



Type I-III, la. 



BIGHT FEMUR OF PTEROPUS. (CELEBES.) NO. 172460, V. S. NAT. MUS. 



Pl. 8, Fig. l(i:l. Sw. Tab. IV 



Antero-iiosterinr diameter of bone, 4 mm.; lateral, 3.5 mm. 



Antero-posteiior diameter of medullary canal, 2.5 mm.; lateral, 2 mm. 



The medullary canal is full. ]\ledullai-y index, 55%. 



Struci lire. — 'j'lie section is comj)Osed of a wide external band of lamelhv 

 divided into two nearly equal concentric rings by longitudinal canals of the (la) 

 differentiation. The lacump are oval and narrow and the canaliculi are straight. 

 Internal circumferential lamellae with long laeiiiiie and straight canaliculi sur- 

 round the medullary canal. 



Type Mil. la. 



