270 BOTANICAL GAZETTE, fOet, 2 
Certain chemical constituents of plants considered in relation to 
heir morphology and evolution.* 
HELEN C. DE 8S. ABBOTT. 
The writer has been engaged for some time upon the study 
of plants by means of proximate qualitative and quantitative 
chemical analysis, in which the latest methods advanced by Dra- 
gendorff were followed. The facts obtained from these studies 
tend to show a chemical progression in plants, and a mutual de- 
pendence between chemical constituents and change of vegetable 
m. 
All plants which were known to contain saponin were exam- 
ined to determine the correlation between this constituent and the 
accompanying morphological forms. It was found that these sa- 
ponin plants occupied the great middle plane of M. Edouard Heck- 
el’s scheme of plant evolution.!. M. Heckel arranges all plants 
within three divisions: 1. Simplicity of floral elements; 2. Mul- 
tiplicity of floral elements; 3. Condensation of floral elements, and 
in addition he bases his theories upon three characters: Filiation, 
adaptation, and progression. These laws as well as the three divi- 
sions of development, are not only elements of test for the great 
divisions, but are to be found in orders, sub-orders and classes. 4t 
is a significant fact that all the saponin groups belong to this middle 
division, or multiplicity of floral elements. Saponin is thus a con- 
structive element in developing the plant from the multiplicity of 
floral «lements to the cephalisation of those organs. It is an in is- 
pensable principle in the progression of certain lines of plants, 
passing from their lower to their higher stages. Saponin is invari- 
‘ably absent where the floral elements are simple ; it is invariably 
absent where the floral elements are condensed to their greatest 
extent. Its position is plainly that of a factor in the great middle 
realm of plant life when the elements of the individual are striving 
‘to condense and thus increase their physiological action and the 
economy of parts. All the great groups which contain saponl? 
“are closely allied and possess other properties in common, 4% 
fibrous or bulbous roots, rootstocks, tubular character of some 
part of the flower, and a climbing tendency in Smilacee and some 
-of the Sapotacee. : 
+ Numerous analogous examples of a correspondence between 
morphology and chemical constituents were advanced, and the 
following conclusions reached : 
Darina eee a 
* Abstract, by the author, ing, 1886 
-Evolution used in the sense pecbeaek rc posicn hans as hemeaeee cain SE. 
~*Les plantes-et la théorie de l’evolution, Revue Scientifique, 13 Mars. 1886. 
