THE TISSUES. 



adjacent systems. In the lamellae adjoining the periosteum and mat- 

 row cavity the canaliculi end respectively in the subperiosteal tissue 

 and in the marrow cavity. The canaliculi of the Haversian lamellae 

 empty into the Haversian canals. 



, ' - " 



- _ - 



- 



' -'-'' ' 



Outer circum- 

 ferential 

 lamellae. 



/- - ----- Haversian or 



concentric 

 lamellae. 



'- Haversian 



^-'- Interstitial 



lamellse< 



Inner circum- 

 ferential 

 lamellae. 



Fig. 83. Segment of a transversely ground section from the shaft of a long bone, show- 

 ing all the lamellar systems. Metacarpus of man ; X 5- 



The lamellae of bone are compose'd of fine white fibrous-tissue 

 fibrils, embedded in a ground-substance, in which they are arranged 

 in layers, superimposed in such a way that the fibrils in the several 

 layers cross at about a right angle, forming an angle of 45 with 



