321 



Haematologists will adopt the terminology proposed by Minot for 

 the mammalian erythrocytes. 



Summary. 



The polymorphonuclear leucocytes of Amblystoma contain gran- 

 ules which have the general character and staining reactions of azurophil 

 granules. They are quite variable in their size, number, and distri- 

 bution in the cell-body. In this respect they resemble the azurophil 

 granules of the mammalian lymphoid cells, but their radial grouping 

 around the centrosphere, their constant appearance in the polymorpho- 

 nuclears, and their great number in any one cell places them nearer 

 the 'special' granules of the higher animals. The lymphocytes of 

 most Amphibia (frog, Cryptobranchus, and other Amphibia described 

 by Werzberg) lose their azurophil granules when they differentiate 

 into polymorphonuclears, and their cytoplasm becomes oxyphilic. 

 In Amblystoma the cytoplasm of the polymorphonuclears remains 

 'lymphoid' in character, while the azurophil granules remain and their 

 numer bis increased. Since the polymorphonuclears seem to have the 

 same function here as in the higher animals, this permanent azurophil 

 granulation must be regarded as an attempt towards the differentiation 

 of a 'special' granulation. 



In Amblystoma all possible intermediate stages between larger 

 lymphocytes and polymorphonuclears are found in the circulating 

 blood, which is contrary to the findings of Maximo w for Axolotl. 



The ,,parachromatin canals" described by Werzberg in the 

 nuclei of the spindle cells of Amphibia are optical appearances pro- 

 duced by deep furrows on the surface of the nuclei. In Amblystoma 

 the furrows are frequently so deep as to give the nucleus a lobulated 

 appearance. 



The erythrocyte nuclei of Amblystoma are more pyknotic and 

 more degenerative in character than those of the erythrocytes of the 

 garter snake. Consequently Minot's division of the erythrocytes 

 of the lower vertebrates into "ichthyoid" and "sauroid" types does 

 not hold in all cases. If his classification is adopted we will have 

 erythrocytes of Ichthyopsidae with "sauroid" nucleus, and erythro- 

 cytes of Sauropsidae with an "ichthyoid" type of nucleus. 



Anat. Anz. Bd. 44. Aufsätze. 



21 



