44 CHEMICAL PHYSIOLOGY. 



alkalies, but the gelatine is distinguished by yielding 

 glykokoll, the lower homologue of leucine, while elastic 

 fibres yield more leucine. Mucine yields sugar by 

 chemolysis, and in this respect resembles chondrine, 

 but it also yields much tyrosine, up to 7 per cent. 

 These various data have given rise to the idea that 

 mucine and glutine were products of a peculiar cleavage 

 of albumen, but albumen has not yet been found to 

 yield any sugar. The cells or corpuscles of the con- 

 nective tissue consist of a semi-fluid matter which is 

 termed the protoplasma, and of nuclei. In the pro- 

 toplasma of the cells of the connective tissue pigment 

 is frequently deposited (choroid, rete Malpighii of 

 negro, bronzed skin disease, freckles, melanotic cancers), 

 which is black or brown. Of this pigment very little 

 is known. 



Fatty tissue. The fat tissue is made up of cells, in the interior of 

 which fat is deposited, and of connective tissue. The 

 fat cells are probably peculiar organs, but the cells of 

 the connective tissue above described are probably able 

 to deposit fat within their substance under certain 

 circumstances. Some fat tissue remains permanently 

 in the body, some may lose its fat during starvation or 

 disease, and regain it afterwards. The fats in the human 

 fat tissue are mostly those described in the paragraph on 

 digestion, namely, tri-stearine, tri-palmitine, tri-oleine. 

 The fatty tissue is subject to hypertrophy, or excessive 

 infiltration; there are also peculiar colorations ob- 

 served in several diseases, (e. </., consumption or 

 phthisis), which are due to an accumulation of luteine. 

 Newly formed fat tissue is observed in the fatty 



