AND ITS RELATION TO ANIMAL LIFE 25 



from an anaemic haemoglobin ; and if this is 

 admitted, as I think it must be, then it follows 

 that the phylloporphyrin and the haema- 

 toporphyrin will, in their relation to each 

 other, pass through the whole gamut of varia- 

 tions that can be obtained in either the 

 chlorophyll or haemoglobin, or both. 



Further, I believe if the chlorophyll of a 

 given pasturage, or any of its derivatives, were 

 tested or compared with the haemoglobin, or 

 any of its derivatives, of animals grazing on 

 the said herbage for a sufficient length of time, 

 that the chlorophyll and the haemoglobin, or 

 any of their derivatives, would be found to be 

 similar or identical when tested by the 

 spectrum. 



Indeed, it seems likely that the time is 

 approaching when spectrum analysis will be 

 employed as the best method of ascertaining 

 the relative value of foods. 



In Encyclopaedia Britannica, vol. xix. p. 48, 

 we read 



i. "In green plants it is only those cells 

 which contain chlorophyll that can absorb 



