18 ANATOMY FOR NUKSES. [CHAP. III. 



rounding the fat drop. As these cells increase in number they 

 collect into small groups or lobules, which lobules are for the 

 most part lodged in the meshes of the areolar tissue, and are 

 also supported by a fine network of blood-vessels. This fatty 

 tissue exists very generally throughout the body, accompanying 

 the still more widely distributed areolar tissue in most parts, 

 though not in all, in which the latter is found. Still, its dis- 

 tribution is not uniform, and there are some situations in which 

 it is collected more abundantly. It forms a considerable layer 

 underneath the skin, in the subcutaneous areolar tissue ; it is 

 collected in large quantity around certain internal parts, espe- 

 cially the kidneys ; it is seen filling up the furrows on the 

 surface of the heart; it is deposited beneath the serous mem- 

 branes, or is collected between their folds ; collections of fat 

 are also common around the joints, padding and filling up 

 inequalities ; and, lastly, fat exists in large quantities in the 

 marrow of the long bones. 



Adipose tissue, unless formed in abnormal quantities, confers 

 graceful outlines upon the human frame ; it also constitutes an 

 important reserve fund, by storing up fatty materials, derived 

 from the food and brought to it by the blood, in such a form 

 and manner as to be readily reabsorbed into the circulation 

 when needed. 



Cartilage. This is the well-known substance called "gristle." 

 When a very thin section is examined with a microscope, it is 

 seen to consist of nucleated cells disposed in small groups in a 

 mass of intercellular substance. This intercellular substance 

 is sometimes transparent, and to all appearances homogeneous 

 or structureless ; sometimes dim and faintly granular, like 

 ground glass : both these conditions are found in what is called 

 " true " or hyaline cartilage, and which is the most typical form 

 of the tissue. There is another variety of cartilage, in which 

 the intercellular substance is everywhere pervaded with fibres. 

 When the fibres are of the white variety, it is called white 

 fibro -cartilage ; when they are elastic fibres, it is called yellow 

 or elastic fibro -cartilage. 



Although cartilage can be readily cut with a sharp knife, it 

 is nevertheless of very firm consistence, but at the same time 

 highly elastic, so that it readily yields to extension or pressure, 

 and immediately recovers its original shape when the con- 



