316 



develop specific granules, and in this respect they may be regarded 

 as incompletely differentiated leukocytes which retain their lympho- 

 cyte charcters to a greater or less degree. In Amblystoma, both the 

 azurophil granules and a considerable amount of the basophilic spon- 

 gioplasm have been carried over from the lymphocyte from which 

 they were differentiated, and for this reason the relations of the poly- 

 morphonuclear to the lymphocyte are more evident in Amblystoma 

 than in most Amphibia. 



That all Amphibia are not alike in this respect is seen from an 

 examination of the pol^^morphonuclears of the frog. Here the proto- 

 plasm is distinctly oxj^philic in its staining reactions, and not a trace 

 of azurophil granulation is to be seen, although many of the lympho- 

 cytes contain the granules. Similar results were obtained from a 

 study of the blood of Cryptobranchus. In both of these animals the 

 cytoplasm of the polymorphonuclears undergoes more complete 

 differentiation than is the case in Amblystoma and at the same time 

 the granules are lost. 



All granules which stain in azure are not identical. In Amblysto- 

 ma this is proven by the fact that some methods which give a good dif- 

 ferentiation of the azurophil granules of the spindle cells will not bring 

 out the granules in the lymphoid cells and polymorphonuclears. For 

 example, it is possible after prolonged fixation in the fumes of osmic 

 acid, or in the fumes of a mixture of osmic, formalin and tincture of 

 iodine, to obtain splendid staining of the granules of the spindle cells, 

 while the same methods do not bring out the azurophil granules of 

 the lymphoid cells and polynuclears. In a recent publication the 

 writer has shown that similar conditions are found in mammals where, 

 with the proper methods, it is possible to stain the azurophil granules 

 of the megakaryocytes and of the blood platelets in sections, while 

 the same methods do not bring out the azurophil granules of the 

 lymphoid ceUs.^) These observations again prove the fallacy of the 

 Ehrlich contention, that all granules staining in the same dye are 

 identical. The different behavior towards fixing fluids of granules 

 having the same staining reaction is alone sufficient to prove that 

 they are not of equal chemical constitution. 



1) According- to Pappenheim and R. Hertz the coarse azurophil granules 

 of the " Lymphoidozj'ten " and " Leukoblasten " of myelogenous leukemia are 

 very different from the azurophil granules of the lymphocytes which are 

 derived from the adenoid tissue. 



