458 MAMMALIA— PHYSIOLOGY 



for the agglutinins, before utilizing the blood of a donor. In 1901, 

 Landsteiner showed that human beings may be divided into three 

 groups according to the interactions of their sera and blood cells. 

 Later his pupils, Decastello and Sturli, added a fourth group. 

 Blood from two persons of the same group will mix freely, but the 

 blood from two different groups will clump or agglutinate. 



Inagglutinable; contain no agglutino- 

 gen. 



Agglutinated by serum of groups O and 

 B; contain agglutinogen A. 



Agglutinated by serum of groups O and 



Landsteiner's Table of the Constitution of the Four Blood Groups 

 Group Serum Cells 



O Agglutinates cells of three other groups; 



contains agglutinins alpha and beta. 

 A Agglutinates cells of groups B and AB; 



contains agglutinin. 

 B Agglutinates cells of groups A and AB; 



contains agglutinin. A; contain agglutinogen B. 



AB No agglutinative effect; contains no ag- Agglutinated by serum of groups O, A, 



glutinin. and B; contain both agglutinogens A 



and B. 



Moss's classification of blood groups has to some extent replaced 

 the earlier ones of Landsteiner and Janksy. Hooker and Boyd 

 of the Evans Memorial Hospital, Boston, have studied (1929) the 

 chances of establishing a child's paternity by blood grouping tests. 

 A child's blood may belong to the same or a different blood group 

 from its mother. Some investigators believe that the characteristics 

 follow the Mendelian Law and may be inherited from the grand- 

 parents.^ 



Lyinph. — Except for those red corpuscles accidentally present 

 in it, lymph may be considered to be blood minus the erythrocytes. 

 Lymph bathes every cell and tissue of the body, and mediates inter- 

 changes between the tissues and circulating blood. It has several 

 important functions: (i) The conveyance of food and of oxygen 

 inward from the capillaries to the cells and the external transporta- 

 tion of the tissues' waste. (2) The absorption of fat from the diges- 

 tive tube. (3) The lubrication of great serous surfaces. (4) The 

 upkeep of fluids in the brain and spinal cord. (5) The maintenance 



^ Consult K. Landsteiner, The Human Blood Groups, pp. 892-908; R. Ottenberg 

 and D. Beres, The Heredity of the Blood Groups, pp. 909-920; in Jordan, E. O., and 

 Falk, I. S., The Newer Knowledge of Bacteriology and Immunology, U. of C. Press, 

 1928; and the summary by L. H. Snyder, Arch. Path, and Lab. Meth., vol. 4, pp. 215- 

 257, 1927. 



