[gg Givynncth Buchanan: 



1 have frequently found them elongated at right angles to the- 

 length of the smear, I adhere to my hist belief that they are fairly 

 usual constituents of the blood of certain animals. 

 2. Leucocytes. 



(a) Lymphocytes. Small, round <>r irregular cells, with 

 basophil and practically homogeneous protoplasm. 

 Deeply basophil nucleus filling the greater portion of 

 the cell. 



(b) Mononuclear. Larger basophil forms, frequently con- 

 taining basophil granules, and with large and often- 

 excentric nuclei. 



(c) Volymorphonucleate. Large forms, with irregular and 



frequently excentric basophil nucleus, the cell proto- 

 plasm often exhibiting faint acidophil properties, or 

 even granules. 



(d) Transitional forms. Basophil cells, whose nuclei pre- 



sent intermediate stages between (b) and (e). 



(e) Eosinophile, containing large or small acidophil granules,. 



and irregular nuclei. 



(f) Mast cells, containing granules, staining more or less 



metachromatically, and faintly basophil cytoplasm. 



Fishes. (Plate XVII 1. ;. Figs. 1-6.) 



Only one form was examined — the teleostean Sea-hedgehog 

 (i)iodon histrix (I)) — and the smear contained many bacteria. 

 Tlic red cells were much rounder than those of batraehians or rep- 

 tiles, averaging 12.5/j. x 9.2ju.. The protoplasm of many took a 

 basic stain. One doubtful spindle form was observed, measuring 

 13. 2 U x 8.3/*.. The lymphocytes were round, and the most con- 

 spicuous leucocytes were mononuclear forms, with deeply basophil 

 granules, averaging 12.4//. in diameter; while others resembling 

 (lie polymorph type in general characteristics, but containing 

 basophil protoplasm, averaged 11.6/a, No eosinophil forms were 

 apparent on treatment with either .leuner's or (iiemsa's stain. 

 l Newton Parker (2) gives the average sizes of the red as much 

 larger (40-46 M x 25-27/*), but Johnston and (Viand (3) remark 

 thai they find a wide diversity among tishes. dipnoi running as 

 high as 2!>/. x 23/a, while in some teleosts their reading is as 



1 Qruner (14) notes that in general the lymphocytes are fairly typical in this group, showing 

 transitions to the large mononuclear type ; also the fact, that, the mononuclear forms aw typical 

 of ti,«- lower vertebrates, occasionally replacing the polymorphs in function, lie also draws atten- 

 tion to the absence of eosinophil and innst cells in fishes. 



