EXPLANATION OF Tlir<: PLATF.S. 
59 
PLATE N.— continued. 
Fig. 5. — Section showing external surface of mantle of Nieuport oyster, showing eosinophiloiis cells 
passing outwards (Zeiss, apochr. 1.5 mm.). 
Fig. 6. — Transverse section of pallial tentacle of Dutch oyster, showing eosinophilous cells (Leitz, obj. 7). 
Fig. 7. — Section of internal surface of mantle of American oyster, showing eosinophilous cells (Zeiss 
apochr. 1.5 mm.). 
Fig. 8. — Another section of the same, to show the ha-matoxylin reaction in the eosinophilous cells. 
Fig. 9. — Large amoeboid granular green leucocytes from the surface of gill and mantle in American 
oyster, with the green leucocytosis, bedded at Fleetwood. The four marked b were fro)n the 
blood, the rest from the surface (Zeiss, apochr. 1.5 mm.). 
Fig. 10. — Leucocytes lying between the liver tubules stained with pure haematoxylin (Zeiss, ^-.i). 
Fig. 1 1. — Transverse section of a gill filament of green " native " from Roach River (Zeiss apochr. 1.5 mm.). 
Fig. 12. — Section of the liver of an American oyster with the green leucocytosis, showing the ha?ma- 
toxylin reaction given by the leucocytes (x 60). 
PLATE VI. 
ILLUSTRATING THE GREEN LEUCOCYTOSIS IN AMERICAN OYSTER.S. 
Fig. I. — A healthy well-grown " East River " American oyster. 
Fig. 2. — The same with shell valve removed from right side, to show the nearly colourless mantle. 
Fig. 3. — A similar American oyster (from Liverpool market. May 17, 1897) with left valve removed, 
to show the green leucocytosis. Engorged green blood channels are seen over the viscera 
and on the mantle edge, and the auricles of the heart are filled with green leucocytes. 
Fig. 4. — Left side of another similar oyster (Liverpool market. May 18, 1897), where the pallial blood 
channels are very completely injected with green leucocytes. 
Fig. 5. — Group of Portuguese oysters {Oshea anotelafa), one of which is opened to show the green 
leucocytosis (July 1897). 
Fig. 6. — An American oyster {O. virginicd) re-bedded at Fleetwood, to show a completely green mantle 
(March 30, 1897). 
Fig. 7. — Another, to show a completely green heart and a bright patch on mantle over viscera. 
Fig. 8. — An English oyster {O. edtilis) from Falmouth (July 3, 1897), to show the ventricle of the 
heart completely green, and the auricles brown. 
Fig. 9.— Small Dutch oyster {O. cduHs\ to show green spots scattered over the mantle and adductor 
muscle (July 26, 1897). 
PLATE VIL 
ILLUSTRATING THE COPPER REACTIONS IN GREEN OYSTER.S. 
Fig. I. — Part of the mantle of a green American oyster (May 27, 1897) showing the engorged blood 
channels and smaller blood spaces in the connective tissue, coloured red-brown after treatment 
with potassium ferrocyanide (Zeiss, 35 mm.). 
Fig. 2. — Two ventricles of American oysters, one (/>) green and one {A) colourless, shown fresh and 
also after treatment with potassium ferrocyanide. 
Fig. 3. — Preparation of blood of green oyster, after treatment with potassium ferrocyanide, to show 
some of the leucocytes coloured red (Zeiss, obj. D). 
