6o OYSTERS AND DISEASE. 



PLATE N\\.— continued. 



Fig. 4. — Small piece of the mantle of green American oyster, after treatment with potassium ferro- 

 cyanide, and then left overnight in clove oil to clear, showing an engorged blood channel 

 stained red (Swift, i inch obj.). 

 Fig. 5. — Section of the mantle edge of green American oyster, showing an engorged blood space, coloured 



after treatment with potassium ferrocyanide. 

 Figs. 6, 7, 8, 9. — Four similar sections of the mantle edge of a green American oyster, showing a large 

 blood space engorged with green leucocytes (Zeiss, 35 mm.). 

 Fig. 6. — Unstained, showing the dull green tint. 

 Fig. 7. — After potassium ferrocyanide. 

 Fig. 8. — After ammonium sulphide. 

 Fig. 9. — After pure haematoxylin. 



PLATE VIII. 



ILLUSTRATING THE HISTO-CIIEMICAL REACTION.S. 



-Leucocytes in the mantle of the American green oyster, unstained (Zeiss, apochr. 2 mm.). 

 -Another part of the same, treated with pure haematoxylin (Zeiss, apochr. 2 mm.^. 

 . — The same, treated with potassium ferrocyanide (Zeiss, apochr. 2 mm.). 

 . — The same, treated with ammonium sulphide (Zeiss, apochr. 2 mm.). 

 -A blood space in the mantle filled with leucocytes, treated with potassium ferrocyanide 

 (Swift, \ inch). 

 Fig. 6. — A similar blood space, treated with pure haematoxylin (Swift, \ inch). 



GEORGE PHILIP AND SON, PRINTERS, LONDON AND MVERPOOI.. 



