210 BLOOD 



The EOSIXOPHILS contain larger spheroidal cytoplasm ic granules 

 which show a special affinity for eosin. They are slightly larger than the 

 neutrophilic granulocytes, and comprise about 4 per cent, of the leuko- 

 cytes of normal blood. 



The BASOPHILS are characterized by an extremely variable polymor- 

 phous nucleus, but especially by their spheroidal and irregular basophilic 

 granules of greatly varying sizes. They occur to the extent of only about 

 0.5 per cent, in the circulating blood. They are of approximately the 

 same size as the eosinophils. Their significance and genetic relationship 

 is uncertain, but they are usually interpreted as degenerating granulo- 

 cytes, the granules being variously regarded as products of nuclear frag- 

 mentation, and as cytoplasmic products of mucoid degeneration. Maxi- 

 mow (Arch. mikr. Anat, 83, 1, 1913), however, regards the 'mast cells' 

 of the blood as specialized kinds of granulocytes, distinct from similar 

 cells of the tissues, and without sign of degeneration. 



Cowdry has demonstrated mitochondria, by vital staining with janus 

 green, in all types of leukocytes, except mast leukocytes, including plate- 

 lets. The lymphocytes and polymorph neutrophils contain them abun- 

 dantly. They are only sparsely present in eosinophils. Mitochondria are 

 said to be totally absent in the erythroplastids of normal adult human 

 blood (Intern. Monatschr. Anat. u. Physiol., 31, 4, 1914). 



P. Ehrlich in a series of communications announced that by coloring 

 the leukocytes with various stains he was able to distinguish by their 

 reaction, several types of granules. These he called ( a ) oxyphil or acido- 

 phil, which were deeply stained by eosin, acid fuchsiii, etc.; (/?) amphophil, 

 which were stained both by eosin, and by dahlia and like dyes ; ( y ) baso- 

 phil, which were stained deeply by dahlia, thionin, etc. ; ( S ) certain cells 

 which neither after staining with eosin, etc., nor with dahlia, etc., could 

 be made to show any granules other than the nodes of cytoreticulum ; ( e ) 

 neutrophil, which can be stained only by a due admixture of acid and basic 

 dyes, as of fuchsin and methylene blue, or the so-called 'triacid mixture' 

 of Ehrlich. 



The demonstration of these characteristics presupposed a division of 

 dyes into three primary classes : 



1. Acid e.g., eosin, orange-G, acid fuchsin, aurantia, erythrosin. 



2. Basic e.g., methylene blue, dahlia, thionin, hematin. 



?). X i' u I nil which are only formed by the interreaction of ex- 

 amples of each of the two preceding classes ; the neutral dye 

 is supposed to arise de novo in such mixtures, as a result of 

 chemical reaction. 



