272 PLANT AND ORGANIC CHEMISTRY 



beet, sugar-cane, sorghum, the fruit groups of the Rosaceae, 1 

 and the sugar maple. 



The sugar of the palms, among the highest of plants with 

 simplicity of floral elements, is very like that of the cane. Since 

 the grasses are the lower of monocotyledons with multiplicity 

 of parts, it is notable that at the meeting-ground between these 

 groups, or at the transition-stage into multiplicity, sugar should 

 occur. The sugar of the palm is very little above the sugar line; 

 it may be considered, in an evolutionary sense, as passing to the 

 cane sugar of these other groups, and as forming the apex of a 

 low triangle, the base being the sugar line already described. 

 The large percentage of grape-sugar in the fig, Ficus carica, 

 occurs in a class very nearly on a line with these cane-sugar 

 plants. 



Glucosides are more especially the compounds of the middle 

 plane of plant development, and are found in the higher mono- 

 cotyledons of this stage, in the lower and some of the higher 

 dicotyledons, and less frequently in the highest of all plants, or 

 under cephalization. The first appearance of a glucoside occurs 

 in the apetalous groups of flowering plants, as quercitrin in 

 Gary a tomentosa, Juglandaceas, or in other hickory varieties; 

 then in the next following orders, as salicin and populin, of 

 the willow and poplar; antiarin, of the Ants jar, or Upas-tree 

 (Antiaris toxicaria] ; acorin, of the Arum, and coniferin, of the 

 Coniferae. Among the Lirioideae groups many glucosides occur, 

 especially saponin, and I have found this compound in species 

 of the yucca, agave, and among dicotyledons in leguminous 

 plants; besides, it is found in Rosaceae and other parallel 

 groups. 



Saponin is also found in Smilax, a genus partaking somewhat 

 of the nature of endogens and exogens, and serves to unite all 

 the saponin groups; 1 and although this compound is widely 

 distributed in plants, it is a significant fact that all the groups 

 containing it belong to this middle evolutionary division. 



Rosoll 2 has found saponin in the cell-sap of living roots of 

 Saponaria and Gysophila, and I have elsewhere called attention 



1 "Chemical Basis of Plant Forms." See p. 232. 



2 Monats. Chem., v, 94; Jahresb. d. Chem., 1884. 



