18 ANATOMY FOR NURSES. [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, though 

 not in all, parts in which the latter is found. Still, its distribu- 

 tion 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, 

 especially the kidneys ; it is seen rilling 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, the fat exists in large quantities in 

 the marrow of 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. 



Retiform and lymphoid tissue. These tissues closely resemble 

 the areolar variety of connective tissue, except that the bundles 

 of fibrils occurring in them are very much finer, and the meshes 

 of the open and fine network are filled with fluid and with 

 lymph cells. The reticular or retiform tissue forms the whole 

 framework of some of the organs of the body, and enters largely 

 into the formation of the mucous membranes. The lymphoid 

 or adenoid tissue composes the greater part of the lymphatic 

 glands, and other allied structures, and is found also in some 

 mucous membranes. These tissues will be more fully described 

 in connection with the organs in which they are found. 



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 



