24 PLANT DISEASE 



no iron, while the haematoporphyrin was from 

 a haemoglobin produced by a food rich in iron, 

 nitrogen, phosphorus and potash. It is, in 

 fact, my contention that the phylloporphyrin 

 and the haematoporphyrin would vary as the 

 soil and food producing them, and that the 

 phylloporphyrin of a chlorophyll containing 

 the maximum of iron and nitrogen would be 

 identical with the haematoporphyrin of a 

 haemoglobin produced by a plant life contain- 

 ing a normal chlorophyll. It is at least a 

 reasonable presumption that a normal chloro- 

 phyll, that is, one containing the maximum of 

 iron, nitrogen and phosphates, or any of its 

 derivatives, would produce different results in 

 the spectrum to those obtained from a 

 chlorotic chlorophyll or any derivatives of it. 

 In the same way, a normal haemoglobin or any 

 derivatives of it would be likely to produce 

 different results in the spectrum to the results 

 obtained from an anaemic haemoglobin or 

 any derivatives of it. 



From these natural assumptions it would 

 follow that the phylloporphyrin obtained from 

 a normal chlorophyll would produce different 

 results in the spectrum to the results obtained 



