54 SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE VOL. 35 



EIGHT FEMUR OF CROTAPHYTUS COLLAKIS. NO. J 21 12, U. S. NAT. MUS. 



PL. 4, Fig. 57. Syn. Tab. II 



Antero-posterior diameter of bone, 1.5 mm. ; lateral, 1 .5 mm. 



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



The medullary canal is full. Medullary index, 80%. 



Structure. — The section is composed of two concentric rings of lamellae 

 surrounding the medullary canal. The external ring has long lacuna and 

 straight canaliculi, the internal, oval lacunae and bushy canaliculi. The section 

 shows the twofold division. 



Type I. 



LEFT FEMUR OF CROTAPHYTUS COLLARIS. NO. J 32 9, U. S. NAT. MUS. 



Pl. 4. Fig. 58. Syn. Tab. II 



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



Antero-posterior diameter of medullary canal, 0.8 mm. ; lateral, 0.8 mm. 



The medullary canal is full. Medullary index, 40%. 



Structure. — The section is composed of two concentric rings of lamellje 

 surrounding the medullary canal. The external has long lacunae and straight 

 canaliculi, the internal, oval lacuna? and bushy canaliculi. The section shows 

 the twofold division. 



Type I. 



RIGHT FEMUR OF AMEIVA EXI^L. (CAYA DE SANTIAGO, POETO RJCO.) NO. L 21 11, 



U. S. NAT. MUS. 



Pl. 4, Fig. 59. Syn. Tab. II 



Antero-posterior diameter of bone, 2 mm. ; latei-al, 2 mm. 



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



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



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

 long lacunae and straight canaliculi surrounding the medullar}^ canal. There is 

 very little differentiation of structure. The section is uniform. 



Type I. 



RIGHT FEMUR OF EUMECES FASCIATUS. NO. H 31 4, U. S. NAT. MUS. 



Pl. 4, Fig. 60. Syn. Tab. II 



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

 Antero-posterior diameter of medullar}^ canal, 0.6 mm. ; lateral, 0.5 mm. 

 The medullary canal is full. Medullary index, 24%. 



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

 canaliculi dimly outlined in laminae. There is little differentiation of structure. 

 Type I. 



