130 STATES IN WHICH FATTY MATTER EXISTS. 



in the next lecture, we find adipose tissue with a 

 mere trace of connective tissue. 



183. State!« in which fatty matter exists in the 

 body. — But before I describe the characters of the 

 fat tissue, it is desirable to refer briefly to the diffei'ent 

 forms or states in^ which fatty or oily substances are 

 found ; for fat exists in the body of man and in the 

 higher animals in several different states. 



In the first place, there is scarcely a fluid or tissue 

 in the organism rf any animal from which more or 

 less fat cannot be extracted by careful analysis. 

 Secondlij, every form of bioplasm yields a minute 

 quantity of fatty matter. Thirdly, in many parts of 

 the body, little j articles (globules and granules) of 

 actual fat can be seen by the microFcope. Such 

 globules are present in immense numbers in every 

 kind of m Ik. They are to be detected in the epi- 

 thelial eel's of the sebaceous glands. Oil globules 

 are embedded in the mucus of the air passages, and 

 are to be detected in the liver eel's of all animals, 

 while in some cases the liver cells seem to consist 

 almost entirely of fat. In disease every tissue in tlie 

 organism may be the seat of deposition of globules 

 of fatty matter. But, lasily, fatly matter, and of a 

 particu'ar kind, is foimed by special bioplasm. It 

 forms the chief constituent of a most important 

 tis'^ue, adipose tissue, which accumulates in many 

 pai-ts, fill'ng up interstices between the muscles and 

 forming, at least in the infant, a tolerably even layer 

 beneath the skin of the body. This layer of sub- 

 cutaneous ad pose tissue varies however in thickness 

 in different parts and at different ages. In some 

 few situatioi s particularly where the skin is very 

 movable over the tissues btneath, as the skin of the 

 eyrlids, there is no adipose tissue at all; or, in other 

 words, the arecL>r or connective tissue in the meshes 

 of which the adipose tissue is usually contained, is 

 in this and some other situations, destitute of that 



