ITS MORPHOLOGICAL CHARACTERS. 15 



sian canals. If we could succeed in collecting the contents of 

 these minute tubes in a state of purity (which is by no means 

 impossible), we should thus have an opportunity of chemically 

 examining a perfect physiological plasma. 



We perceive, from this short notice of the different systems of 

 cavities which penetrate bone,, and of the variety of their contents, 

 that even in analysing bones that have been long and carefully 

 macerated, we are dealing with not only the true osseous substance, 

 but with other matters, as, for instance, the remains of the con- 

 tents of the various canals, &c. 



But before proceeding to the chemical consideration of the 

 bones, we have still to determine the question whether the true 

 matrix (independently of the contents of these canals) is a thoroughly 

 homogeneous mass, that is to say, whether, morphologically con- 

 sidered, it exhibits a perfectly homogeneous continuity, and whether 

 in a chemical point of view, it can be regarded as a perfectly 

 uniform material, that is to say, as a chemical compound of certain 

 proximate constituents. 



The matrix of bone is found on a careful microscopical examina- 

 tion to be far from perfectly homogeneous. In the first place, on 

 examining well-prepared transverse sections, we perceive a number 

 of concentric circles surrounding the section of each Haversian 

 canal. These circles are true lamellae, varying in thickness from 

 0-002 to 0'005"' (Kolliker).* Besides these lamellae connected with 

 the Haversian canals, there is also a general system of such plates 

 which correspond to the outer and inner surface of the bone, and 

 are parallel to these surfaces. (Kolliker^s Fundamental Lamellae.) 

 Associated with these and interspersed here and there in the inte- 

 rior of the bone between the lamellae of the Haversian canals, are 

 isolated groups of parallel lamellae. (Koiliker's Interstitial Lamellae.) 

 These are most distinctly seen in sections of bone that have been 

 carefully treated with dilute hydrochloric acid ; but they may also 

 be recognised in incinerated bone. But even the individual 

 lamellae, independently of the very minute tubules occurring in 

 them (the bone-corpuscles with their prolongations), are not by any 

 means homogeneous : we remark in them an extremely fine punc- 

 tated appearance, depending on the presence of innumerable pale 

 granules of nearly uniform size (according to Kolliker, about 

 0-0002'") . Kolliker is inclined to regard these granules as identical 

 with the angular corpuscles which Tomes found in the fragments of 



* Mikrosk. Anat. Bd. 2, S. 288. 



