Chap. IV] CONNECTIVE TISSUES 41 



with bundles of white fibres, between which are scattered cartilage 

 cells. It closely resembles white fibrous tissue, and is found 

 wherever great strength, combined with a certain amount of rigid- 

 ity, is required. 



Yelloiv, or elastic, fibro-cartilage. — The intercellular substance 

 is pervaded with yellow elastic fibres which form a network. 

 In the meshes of the network the cartilage cells are found. 



Function. — The function of cartilage is roughly the same 

 throughout, the qualifying terms are used to denote differences in 

 structure and appearance rather than in function. 



1. Hyaline cartilage covers the ends of the bones in the joints, 

 where it is known as articular cartilage. 



2. Hyaline cartilage forms the rib cartilages, where it is known 

 as costal cartilage. 



In both these situations the cartilages are in immediate connec- 

 tion with bone, and may be said to form part of the skeleton, 

 hence frequently described as skeletal cartilages. 



The articular cartilages, in covering the ends or surfaces of 

 bones in the joints, provide these harder parts with a thick, springy 

 coating, which breaks the force of concussion, and gives ease to 

 the motion of the joint. The costal cartilages, in forming part of 

 the solid framework of the thorax or chest, impart elasticity to its 

 walls. Hyaline cartilage also enters into the formation of the nose, 

 ear, larynx, and trachea. It strengthens the substance of these 

 parts without making them unduly rigid, maintains their shape, 

 keeps open the passages through them where such exist, and gives 

 attachment to moving muscles and connecting ligaments. 



White fibro-cartilage is found joining bones together, the most 

 familiar instance being the flat, round plates or disks of fibro- 

 cartilage connecting the bones of the spine and the pubic bones. 

 In these cases the part in contact with the bone is alw^ays hyaline 

 cartilage, which passes gradually into the fibro-cartilage. 



Yellow, or elastic, fibro-cartilage is found in the epiglottis, carti- 

 lages of the larynx. Eustachian tube, and external ear. 



Cartilage is not supplied with nerves, and very rarely with 

 blood-vessels. Being so meagrely supplied with blood, the vital 

 processes in cartilage are very slow, and when a portion of it is 

 absorbed in disease or removed by the knife, it is regenerated 

 very slowly. A wound in cartilage is usually at first healed by 



