1910.] TUE BI>OOD OF GllOIJSE. 727 



The shape of the eosinopliile leucocyte is round (figs. 14, 15) or 

 somewhat (juadrilateral (tig. 18). Tlie general cytoplasm is pale 

 staining and slightly reticulate in structure. The nucleus usually 

 resembles that of the polymorphonuclear leucocyte, and is mostly 

 bilobed — the lobes being coarsely reticular and usually staining 

 fairly deeply. The cell-body contains numbers of coarse, oxyphile 

 (acidophile) granules which stain deeply with eosin. The granules 

 are often rounded (figs. 13-15) ; they vary in size, some eosinophiles 

 containing large gi-anules (fig. 13) which may be relatively fewer 

 in number, while in other cases the granules are small (fig. 14), 

 and may be I'elatively more numerous. Eosinophiles with large 

 granviles ai^e the more prevalent. The contour of the griimiles is 

 generally round, but sometimes cells containing somewhat ovoid 

 granules are seen which stain intensely with eosin. 



Occasionally eosinophile cells are found in stained films the 

 granules of which vary in shape within the same cell, some being 

 i-ound, some ovoid, and some almost spindle-shaped. Such cells 

 and their contained gi-anides may be somewhat deformed in the 

 making of the film, otherwise it is dilficult to classify these cells 

 which are intermediate between crystalloid (polymorphonuclear) 

 and granular eosinophiles. 



Mononuclear eosinophile cells are occasionally seen in the 

 blood of noi-mal grouse, and perhaps represent an early stage 

 of development of the polymorphonuclear eosinophiles. Such 

 mononuclear cells are somewhat smaller than those de2)icted in 

 PI. LXIII. figs. 13-15, and have round nuclei. They are rare, 

 and are perhaps analogous to the young eosinophile myelocytes 

 of man. 



5. Mast cells (coarsely graiiular basophile cells) are present in 

 the blood of normal grouse (figs. 16, 17). They are rare. The 

 cells ai"e more or less rounded, with a pale staining cj^toplasm. 

 The nucleus is usually rounded (fig. 17) or slightly polymorphous 

 (fig. 16), and stains blue with Jenner's stain — rather more deeply 

 than similar cells in mammals. 



Basophile granules, which vaiy in size and in number, occur in 

 the cytoplasm. The granules are usually rounded and stain a 

 deep purplish colour with Jenners stain — in otl\er words the 

 granules are metachromatic. Mast cells measure from 9, /.« to 

 1U"5 /x in diameter. 



(c) Thromhocytes also occur in the lilood of grouse (fig. 4). In 

 the fresh condition they suggest very narrow and slightly small 

 ei-ythi-ocytes. They aie often elliptical, with an oval nucleus 

 centrally placed. 



When stained the cell-body is pale and vacuolated, suggesting 

 a coarsely reticular cytoplasm. The whole cell is basophile in its 

 reactions, staining rather faintly blue with Jenner's stain. 



Thrombocytes in grouse aveiage 9 fi by 4 ^. 



