HIGHER AND LOWER PLANTS 267 



chemistry, I will mention that sugar is not, in all plants, a 

 reserve or plastic body, and in some few (for example, the 

 sorghum cane *) it must be regarded rather as a waste pro- 

 duct, and its advent in larger percentage after the maturity of 

 growth marks the decay of the plant and attends its euthanasia. 



I have desired, by entering into all of the above particulars, 

 to prepare for a consideration of the compounds which are 

 formed by these chemical successions and occur through the 

 plant kingdom. In treating of this subject I shall have so fre- 

 quent occasion to speak of the different plant families that, for 

 convenience, I shall use the order of evolution for flowering 

 plants^ proposed by M. fidouard Heckel, 2 and which is repre- 

 sented in the table. 



The author classes all these plants under three main parallel 

 divisions, from the lowest of the apetalous, 3 mono- and di-coty- 

 ledonous groups to their respective highest plants. These three 

 main columns are divided at the same point into three general 

 planes. On plane i are all plants of simplicity of floral elements 

 or parts; for example, the black walnut with the simple flower 

 contained in a catkin. On plane 2 are plants of multiplicity of 

 floral elements, as the many petals and stamens of the rose; 

 and, finally, the higher plants, as the orchids among the mo- 

 nocotyledons, and the Composite among the dicotyledonous 

 plants, come upon the third plane, or the division of conden- 

 sation of floral parts. 



These three characteristics, simplicity, multiplicity, and con- 

 densation of floral elements, are correspondingly repeated in 



" On the Variations of Sucrose in Sorghum Saccharatum," by H. W. Wiley, 

 Botanical Gazette, vol. xii, March, 1887. 



2 Revue Scientifique, March 13, 1886. 



3 Heckel's division of apetalous plants from mono- and di-cotyledonous 

 groups has been criticised by some botanists as an artificial method of classi- 

 fication. Since all botanical classifications have been declared, on botanical 

 authority, in a measure artificial, the author does not feel called upon to 

 apologize for introducing M. Heckel. She has found his scheme to answer 

 her purposes, provisionally, more fully than other classifications, and she is 

 indebted to him for a means of presenting her subject which would be other- 

 wise impracticable. Further than this she is not responsible for advocating 

 the classification. M. Heckel's table is published with his paper, "Les Plantes 

 et la Theorie de FE volution," in the Revue Scientifique, March 13, 1886. 



