446 REPORT — 1901. 



in extracts o£ animal tissues was of considerable service if used in dilute 

 solutions on the protophytan cell. It consists of a mixture of a-naphtol, 

 paraphenylendiamin, and soda in the proportions by weight of 12, 9, 

 and 10, and when freshly made should have only a slight yellow-red 

 tint ; but on exposure to the air for some hours it gradually becomes violet 

 and then blue, due to the formation of indo-phenol. The reactions which 

 occur thus and in the cell may be indicated as follows : — - 



(«) C6H4(NH2)o + C,oH,OH + 0=NH +H,0 



^-C,3H4NHo CoH.NH, 



(b) NH +0 =]sr ^-__ " +H2O 



"When the reagent is poured on the fresh protophytan threads and allowed 

 to act on them for 20-30 minutes, or even for 2-3 hours, the fluids in 

 the cell spaces {Sinrogyra, Ordogonium, »fec.) are often coloured violet 

 blue, and contain small sheaves of the blue crystals of indo-phenol. 

 This indicates the occurrence of oxidising enzymes in the fluids of the 

 cell spaces or cavities, but no coloration was found in the protoplasm 

 itself or in the nucleus, and the chromatophor itself gave only a very 

 faint reaction in a few cases, except in the immediate neighbourhood of 

 the pyrenoids, when frequently a deeper reaction was observed. That 

 the blue reaction was not due to the diffusion of the colouring material 

 from other points is indicated by the fact that indo-phenol, to which the 

 blue colour is due, is almost insoluble. It is to be noted that in the 

 report of last year the conclusion that the chromatophor contains no 

 oxidising enzymes was based on the fact that that organ did not appear 

 to be atfected when extracts of the enzymes were made by hydraulic 

 pressure from the cells. This conclusion, in view of the fact given above, 

 must now be considered untenable. Tlie reagent was also employed on 

 the Cyanophycesc to determine the presence of oxidases in these non- 

 nucleated forms, and it was found that one is present in the peripheral 

 coloured zone and its granules in these cells, but the ' central body,' 

 which is considered by some to be the homologue of the nucleus of the 

 higher forms, is absolutely unaflected, as are also its granules, by the 

 reagent. The peripheral zone would appear to correspond to the cell 

 fluids and chromatophor of higher Protophyta, while the ' central body,' 

 so far as absence of an oxidase is concerned, corresponds to the nucleus 

 and cell protoplasm of Spirogyra. 



The reagent cannot be used to detect the peroxidases, so that the 

 micro-chemical localisation of these enzymes could not be determined. 

 The difficulties in the employment of solutions of guaiacum for this pur- 

 pose on fresh cells, or even on alcoholic preparations of them, were found 

 to be insuperable. 



The main point to be noted in all these observations is that the oxi- 

 dases are not components of the living framework of the cells, but are 

 dissolved in the fluids which bathe that framework and circulate in the 

 cell spaces and cavities. In consideration of the relations which these 

 fluids bear to the surrounding media it would seem proper to regard these 

 oxidases, not as enzymes, but as oxygen-carriers, playing the part in the 

 cell mechanism that htemoglobiu does in the animal body. 



