202 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



leucocytosis are always more or less green, but must not be 

 confounded with ordinary green-gilled Oysters, where the 

 colour is due to a totally distinct cause. Later in the 

 summer, at the Toronto meeting of the British Associa- 

 tion, we gave a further account of our investigations up 

 to date, and from that report I quote the following account 

 of the micro-chemical part of the work * : — • 



" The following are our details of the histo-chemical 

 investigation of the pigment. The green pigment is 

 in soluble in boiling alcohol, ether, chloroform, xylol, and 

 other fat solvents ; it is soluble in dilute acids and alkalies. 

 The addition of potassic ferrocyanide to sections contain- 

 ing the green colouring matter, or to the leucocytes 

 themselves, gives a red reaction, indicating the presence 

 of copper ; but the reaction can be most readily obtained 

 by the addition of a small quantity of '5 per cent, hydro- 

 chloric acid to the potassic ferrocyanide. Ammonium- 

 hydrogen sulphide gives also an immediate reaction with 

 the green pigment. Ammonia strikes a beautiful blue 

 wherever there is a green. It was then found that pure 

 hematoxylin is an extremely delicate test, giving an 

 immediate blue reaction in exceedingly dilute solution. 

 Previous treatment of the green colouring matter by 3 per 

 cent, nitric acid in alcohol prevented these reactions, and 

 subsequent treatment with acidulated potassic ferrocyanide 

 resulted in a very faint general prussian blue colouration 

 of the tissue generally. We concluded that there was no 

 inorganic iron present in the leucocytes, that the leuco- 

 cytes which form the green patches contain a considerable 

 quantity of copper, and that, just as in the case of iron, 

 as shown by Professor Macallum, pure hematoxylin is a 

 most delicate test, but that great care must be taken, to 



* For further details on some points see Proceedings of Royal Society, 

 vol. LXIL, p. 30, 1897. 



