THE BEGINNINGS OF IIFE. 425 



of some of the more striking metamorphoses. It must 

 be recollected, that in all the aquatic plants in which 

 these changes have been noticed, the chlorophyll cor- 

 puscles become incorporated with the protoplasmic sub- 

 stances, and so help to constitute the spherical masses 

 out of which the new organisms are to be evolved. 

 But chlorophyll is a most complex and unstable body, 

 well calculated to excite even more metabolic changes 

 amongst the protoplasm than would otherwise occur ^. 

 M. Fremy describes it as a substance, '^ d'une excessive 

 mobilite,^ so that its mixture in different proportions, 

 leading to slight differences in the molecular changes 

 induced^ would be likely to give rise to variable results 

 in the metamorphic processes taking place within the 

 same vegetable cell or algoid filament, or within similar 

 filaments on different occasions 2. 



^ These masses of matter are indeed so unstable and so prone to 

 undergo change that I have found it quite impossible to preserve them 

 unaltered as microscopical specimens — although I have tried almost 

 every known means of mounting them. They soon lose theii colour 

 and all their characteristic appearances ; and yet when the tissues of 

 higher animals are mounted in some of the same fluids they will remain 

 comparatively unaltered for years. 



- ' Compt. Rend.' 1865, p. 188. According to Fremy, chlorophyll is 

 a peculiar sort of coloured fatty substance which undergoes a kind of 

 saponification under the influence of bases ; leading to the production of 

 phyllo xanthine, a yellow neutral body, and" a bluish-green fatty acid, 

 which he proposes to name phyllocyanic. This latter substance, insoluble 

 in water, is soluble in sulphuric and hydrochloric acids — producing 

 liquids which, according to circumstances, may be green, reddish-violet, 

 or of a most beautiful blue colour. M. Fremy says : — ' Voici done un 

 acid retire de la chlorophylle et qui par Taction de certains reactifs peut 



