EXPLANATION OF THE PLATES. 



PLATE XXXII. 



STRUCTURE OF BONE. 



Fig. 1. A transverse section of ulna, magnified 60 diameters, 

 showing the Haversian canals, the difference in the 

 size of those situated on the outer and inner por- 

 tions of the section, the systems of the lamellae by 

 which each canal is surrounded, and the bone cells 

 placed between the lamellae. 



Fig. 2. Cross section of Haversian canals, magnified 220 

 diameters, showing the lamellae and the bone cells 

 with their anastamosing canaliculi more distinctly. 



Fig. 3. The same, still more highly magnified, viz. 670 

 diameters. 



Fig. 4. Longitudinal section of long bone, magnified about 

 40 diameters, showing the Haversian canals, seen 

 lengthways, the direction of the lamellae and the 

 bone cells. 



