138 GENERAL ANATOMY. 



transudation: the sebaceous follicles are too well known at 

 present, to permit us to adopt this idea. The general uses of 

 the fat relate to nutrition. Previous to being assimilated, the 

 nutritive matter passes successively through various states; 

 fat is one of the forms it assumes. Moreover, this fluid may 

 be considered as an aliment in reserve: of this various exam- 

 ples are seen in animals. Insects for instance are nourished 

 by their fat while in their chrysalis state, and present the same 

 phenomenon a little time before their death. This is still 

 more strongly marked in the hybernating animals which sleep 

 during the winter, and are nourished by their fat only, until 

 they wake, at xvhich period they are excessively lean. The 

 foetus of the oviparous animals are nourished by the fat which 

 forms a great proportion of the yolk of the egg. 



169. The adipose tissue and the fat, besides the differ- 

 ences of which we have spoken, present some morbid changes. 



When the fatty tissue is divided, small drops of oil escape 

 and if the lips of the wound are maintained in contact, reunion 

 soon takes place; but the fat reappears in the place of reunion, 

 only, when the new cellular tissue has ceased to be compact. 

 The denuded fatty tissue becomes inflamed, the fat is absorbed ; 

 it then covers itself with a layer of organizable matter, which 

 becomes the base of the cicatrix or new skin that is formed 

 over the fat. 



This tissue and the fat it contains sometimes accumulate in 

 great quanities, as is seen in obesity or polysarca. Individuals 

 have been seen in this state weighing five or six and some- 

 time eight hundred pounds. When the obesity is local, or 

 limited to a part of the body it is called Jipoma.* This dis- 

 ease may have its seat any where; it is most commonly seen 

 however under the teguments, and outside the serous mem- 

 branes. Tumours of this kind seated under the skin, have 

 been very improperly confounded with encysted tumours. 

 Their figure is round; when very voluminous they push up 

 and draw away the skin, and are then pediculated or pyriform: 



* See Th. Ch. Bigot Dissert, sur les tumeurs graisseuses exterieur au pe~ 

 ritoine, etc. Paris, 1821. 



