78 CHEMICAL CONSTITUENTS OF ABNORMAL SECRETIONS. 



of the spleen, liver, pancreas, lungs, brain, thymus, and 

 thyroid glands ; but whether it exists in the healthy 

 living body as such, or is only a morbid product of de- 

 composition, is not yet a settled question. Be that as 

 it may, one thing is quite clear viz., that its quantity 

 is vastly increased during disease, and that its appear- 

 ance in some of the excretions is a diagnostic sign of 

 considerable importance and of great value. 



Secondly, Tyrosine belongs to the same class of sub- 

 stances as Leucine. It differs, however, from the I 

 by its being crystallizable, and when pure it crystalli/'-s 

 in line white. glistening, stellate groups of small prisms ; 

 or very thiekly-set stellate groups of fin --S OF 



spiculated balls, not unlike a rolled-up hedgehog, with 

 the bristles sticking "Ut in all directi<>: 



Chemically, it is similar t" L8UGUI4 DIM hundred 



. 52-67 



o\ ;i . . . . 26-52 

 m , 



Jhdiogen . . . 6-08 



100-00 



Tyrosine is an odourless, tasteless sul.-tance, but 

 when burned gives oil' an un: 'ling vapour. 



It is soluble in acids, alk ! boiling water ; it is 



insoluble in cold water, ether, and alcohol. 



The most simple test for the detection of ie is 



that proposed by Scherer namely, to inuisten B 



ds with strong nitric acid on a spatula, and slowly 

 evaporate to dryness. The residue, which is of a line 

 rich yellow colour, when moistened with hydrochloric 



