4 CALIFORNIA ACADEMY OF SCIENCES. [zd Ser., 



Page. 



Homology of the Plasmocytes and Plasmocytoblasts 30 



Different Kinds of Plasmocytes 31 



The Spheres of the Plasmocytes 32 



Food Supply in the Somosphere 35 



Unequal Staining of the Archosomal Spheres 36 



Absence of a Cell Membrane 37 



Absence of Nucleus 37 



Degeneration of the Plasmocytes 38 



Abnormal Plasmocytes 38 



Amoeboid Movements 39 



Growth a?id Phagocytosis 41 



Duplicity of the Plasmocytoblasts 42 



The Ultimate Fate of the Plasmocyte 43 



Adhesive Nature of the Cytoplasm 44 



XII. The Independence of the Archosome 45 



Identification of the Spheres 51 



Plasmocyte and Leucocyte 57 



XIII. Summary 58 



Measurements of Corpuscles 63 



Bibliography 64 



Explanation of the Figures 66 



Stains 72 



I. Introductory. 



The elements, or corpuscles, of the blood of Batrachoseps 

 attenuattis are highly interesting, differing as they do in 

 several important points from the corresponding elements of 

 the blood of all other batrachians of which I have any 

 knowledge. Batrachoseps attenuattis is one of the most 

 common species of the order in this part of California, and 

 material for study may be had at any time of the year and 

 almost anywhere. Not only do the red cells of the blood 

 vary enormously in size and shape, but they differ also from 

 the blood of other batrachians in the fact that very few of 

 them are nucleated. But the most interesting feature of the 

 blood is the presence of a new corpuscle, which I have 

 termed plasmocyte. In this paper I expect to prove that 

 these plasmocytes are the remnants of the extra-nuclear 

 part of fusiform corpuscles; that they consist of the 

 archosome — archoplasm and centrosomes — which has sur- 

 vived, while the nucleus has been destroyed; that this 

 archosome has surrounded itself with various envelopes 



