104 



STUDIES IN ADVANCED PHYSIOLOGY. 



Three fairly distinct types of cartilage occur, the hya- 

 line, the yellow elastic and the white fibrous. In the hya- 

 line cartilage, as the name suggests, the matrix seems en- 

 tirely homogeneous ; that is, devoid of any fibrillation. In 

 this structureless material the cartilage cells are imbedded. 

 A view held by some histologists that this apparently struc- 

 tureless matrix is permeated by a system of very fine canals , 

 lacks verification. Such hyaline cartilage is found regularly 

 at the ends of bones, where a smooth, articulating surface 

 is necessary. The yellow elastic cartilage differs from hya- 

 line in having the matrix made up of densely packed yellow 

 elastic fibres, in the close meshes of which the cartilage 

 cells are lodged. Such cartilage occurs in the ear and the 



Fig. 47. YELLOW ELASTIC CONNECTIVE 

 TISSUE FIBRES. (After Sharpey.) 



Fig. 48. YELLOW ELASTIC CARTILAGE 



FROM THE EAR. 



tip of the nose, and is peculiarly well adapted to admit 

 slight alterations in position or form. The white fibrous 

 cartilage, as the name suggests, is composed of a matrix of 

 closely pressed white fibres, with the contained cartilage 

 cells packed between them. Such cartilage is found in 

 many places as disks between articulating bones ; it binds 

 together contiguous bones forming connecting fibres between 



