*&73'] Comparative Vegetable Chromatology. 463 



the facts so far determined, and to give a tabular view of 

 the manner in which some of the different classes of plants 

 should be arranged, so as to be in the order of the most 

 simple continuity. This table, of course, refers only to the 

 chromatological characters, and s'ince we could scarcely 

 expect them to follow the same order as the structure, we 

 cannot be surprised to find that the order of arrangement is 

 not exactly the same as that so commonly adopted, and yet 

 the general agreement is sufficient to show that a similar 

 great principle is common to both. 



Actinia* 



Anthea cereus, var. smaragdina. 



Olive group of Algce. 



Red Algce. Oscillatorice. 



Porphyra. Peltigera. 



Green Algce. Lichens. 



Higher Cryptogamia. 

 Highest classes of plants. 



It was some time before I could understand how fungi 

 should be placed in this arrangement, for they could not be 

 inserted anywhere in the direct series. At length I found 

 that on the whole their most prevalent colouring matters 

 correspond with those characteristic of the fructification of 

 lichens, and that fungi, therefore, bear much the same rela- 

 tion to lichens that the flowers of a leafless parasitic plant 

 bear to the foliage of the highest class of plants. This con- 

 clusion, derived from the study of the colouring matters, 

 agrees so well with what has been deduced from other quite 

 independent data, connected entirely with structure, that it 

 must be looked upon as additional evidence of an important 

 relation between the general organisation of plants and 

 their coloured constituents; which unites with other facts in 

 showing that they are not mere chemical products, formed 

 under such conditions as can be imitated artificially, but in 

 some way or other depend on structure, or on forces 

 connected with it in living organisms. 



My attention has lately been directed to the study of the 

 changes which occur during the growth of the various organs 

 of plants. For example, I have compared the constitution of 

 the endochrome of the petals, when in a rudimentary state, 

 with that of leaves and fully developed flowers. Even so 

 far the results are of much interest. The endochrome of 

 the rudimentary petals approximates in character to that of 

 leaves; and, during their development, this leaf-like character 

 is gradually lost, and often new colouring matters are formed. 

 Differently coloured varieties are often simply cases in which 

 this development is arrested, so that some, when fully grown, 



