OSSEOUS SYSTEM. 179 



Q. Are the bones larnellated in their compact structure ? 



Ji. They are not. If they exfoliate in scales, it is by 

 an abnormal process, not by the separation of the natural 

 structure; again, exfoliation does not always assume the 

 form of scales or layers, for it sometimes takes place in a 

 direction differing from the course of the supposed layers. 

 The structure is one of condensed fibres. 



Q. What is Beclard's opinion as to the laminated struc- 

 ture of the bones in general? 



#. He thinks, that from a general view of experiments, 

 that the structure is laminated, connected with fibres, and 

 with small areolated spaces abounding between laminated 

 fibrous structure. 



Q. How does a bone become affected with rachitis? 



*#. In some degree by the absorption of the phosphate 

 of lime, perhaps too by a diminished exhalation of it; 

 but this diseased state arises principally from a separation 

 of the osseous fibres from each other, by which a cellular 

 instead of a compact bony texture is formed. 



Q. What is the usual general arrangement of the spongy 

 and compact texture of the bones? 



#. The compact texture is the exterior, and the cellu- 

 lar the interior part of the bone. 



Q. Is there no exception to this rule? 



ft. It is inverted in the case of the spongy bones of the 

 nose. 



Q. Where is the compact texture of the long bones 

 greatest? 



.#. It is greatest in the middle of the bones. 



Q. And why. is it so ? 



#. That it may give solidity to the bones, and enable. 



