:,7i; 



AN AMERICAN TEXT-BOOK OF PHYSIOLOGY. 



Albumins 



neutral or acid solutions. Proteid is also precipitated by tannic acid in acetic- 

 acid solutions, by phospho-tuugstic and phospho-molybdic acids in the presence 

 of free mineral acids, by picric acid in solutions acidified by organic acids. 1 

 The precipitation of proteid is also accomplished by nucleic acid, taurocholic 

 acid, and chondroitic sulphuric acid in acid solutions. 



Of the eohr-readions the action of Millon's reagent has been described 

 p. 569). Soluble proteids give the biuret test (see p. 549). With concen- 

 trated sulphuric acid and a little cane-sugar a pink color is given when proteid 

 is present (see p. 544). Proteid heated with moderately concentrated nitric 

 acid gives yellow Makes, changing to orange-yellow on addition of alkalies 

 (xantho-proteid reaction). Proteid in a mixture of one part of concentrated 

 sulphuric acid and two parts of glacial acetic acid gives a reddish-violet color 

 (Adamkiewicz), a reaction accelerated by heating. Finally, proteid dissolves 

 after heating with concentrated hydrochloric acid, forming a violet-colored 

 sol i i tion ( Lieberman n) . 



The following, taken in part from Chittenden, 2 is submitted as a general 

 classification of the proteids : 



Simple Proteids. 

 Serum-albumin ; 

 Egg-albumin ; 

 Lacto-albumin ; 

 Mvo-albumin. 

 Serum-globulin ; 

 Fibrinogen ; 

 Myosin ; 

 Myo-globulin ; 

 Paramyosinogeu ; 

 Cell-fflobulin. 

 Acid-albumin ; 

 Alkali-albumin. 

 Proteoses and Peptones. 



Coagulated Proteids < ' .. 



I Other coagulated proteids. 



Combined Proteids. 

 Haemoglobin ; 

 Histo-hsematins ; 

 Ckromo-proteids J Chlorocruorin ; 

 Haemerythrin ; 

 Haemocyanin. 



Glyco-proteids < _ _ ' 



* { Mucoids. 



1 The above list is given by Plammarsten, Physiological Chemistry, translated by Mandel, 

 p. IS. 



- " Digestive Proteolysis," Cartwright Lectures, 1895, p. 30. 



Globulins 



Albuminates 



