CHAPTER III. 

 Cartilage Bone Teeth. 



SECT. I. CARTILAGE. The tissue known as cartilage 

 consists of cells of characteristic appearance imbedded 

 in a peculiar material which we shall designate, as 

 the fundamental substance of cartilage. This latter 

 exists in two forms, the one entirely structureless, the 

 other distinctly fibrous; hence the two varieties of 

 the tissue : true cartilage and fibro-cartilage. 

 cartilage ceils. The perfectly formed cartilage cell, such as we find, 

 for example, in the interior of an adult costal cartilage, 

 is usually spherical, or many-sided, and of conside- 

 rable volume (sVth roth of a line), It consists of an 

 external envelope with transparent granular contents, 

 presenting no peculiar features; but the nucleus is 

 filled with large sized oil-globules to such an extent 

 that no nucleolus is distinguishable (PL V. fig. I). 

 Sometimes even the granular contents of the cell are 

 replaced by these oil-globules so completely as to 

 give it the appearance of a vesicle filled by a drop of 

 oil. In childhood, and on the surface of the cartilages 

 of the adult, the cells are of smaller size and elongated 

 in shape, and contain very little free fat, especially in 

 the foetus. 



But the distinctive characteristic of the cartilage 

 cell is the existence of a structureless membrane, or 

 capsule, which surrounds it completely on all sides, 

 and which is continuous bv its external surface with 



