NO. 3 COMPARATIVE 1 1 ISIOI.OGV OK FEMUR FOOTE 133 



The posterior wall is composed entirely of Haversian systems of the (C) 

 dift'erentiation. 



Type II-IIl, C. 



LEFT FEMUR OF URSUS MARITIMUS. TOLAR BEAR. NO. 35085, AMER. MUS. NAT. HIST. 



Pl. 17, Fi(i. 2f)5. Syn. Tab. AMI 



Antero-posterior diameter of bone, 31 mm.; lateral, 38 mm. 



Antero-posterior diameter of mednllary canal, 18 nnn.; hiteral, 22 nmi. 



The medullary canal is full. IMeduUary index, 51%. 



Structure. — The section has a rather x)eculiar shape. With the exception 

 of the posterior ridge it is surroun<led by lamina^, which, in the anterior wall, 

 merge into lamellae and are interrupted by Haversian systems. The central ring 

 is composed of concentric rows of well developed Haversian systems alternat- 

 ing with laminae, excepting in the posterior ridge which is all Haversian systems. 



Internal circumferential lamellae form a narrow ring around the medullar} 

 canal. The bone is nu)re highly differentiated than the femur of the black bear. 



Type II-III, C. 



RIGHT FEMUR OF BUBALIS JACKSONI. HARTEBEEST. NO. 37815, AMER. MUS. NAT. HIST. 



Pl. 17, Fig. 266. Syn. Tab. VII 



Antero-posterior diameter of bone, 32.5 mm.; lateral, 30 mm. 



Antero-posterior diameter of medullary canal, 17 mm.; lateral, 16 mm. 



The medullary canal is full. Medullary index, 39%. 



Structure. — The section is composed mostly of laminae. Around the bone 

 is a wide horseshoe band of laminae, interrupted bv Haversian systems. The 

 band forms the whole of the outer and anterior walls. Underneath the baud in 

 the inner wall is a narrow crescent of well developed Haversian systems. The 

 posterior wall is composed of Haversian systems and short laminae, between 

 which are several vascular canals. A narrow ring of internal circumferential 

 lamellae, slightly wider in the inner wall, surrounds the medullary canal. The 

 lacunjp are long and oval. 



T.ype II-III, C. 



LEFT FEMUR OF PHACOCHCERUS AFRICANUS. WARTHOG. NO. 27762, 



AMER. MUS. NAT. HIST. 



Pl. 17, Fig. 267. Syn. Tab. Vll 



Antero-posterior diameter of bone, 24 mm. ; lateral, 20.5 mm. 

 Antero-posterior diameter of medullary canal, 14 mm. ; lateral, 12 mm. 

 The medullarv canal is full. Medullary index, 52%. 



