stituents, all resources go to develop the perfection of the flowe 
and the absence of numerous compounds in these plants is 
strong point in favor of chemical evolution favoring plant devel 
opment. These beautiful ‘plants being among the highest o 
_ their series, may well be called the aristgcrats of the vegetabl 
kingdom. ey 
It is still impossible to demonstrate the full significance of this 
chemical theory in plant development, but it will be evident 
any one who examines botanical and chemical facts that the | 
presence of certain chemical compounds is associated with or 
tain botanical conditions, and where these conditions are variable, 
is found a like variability of chemical composition. If it canbe 
proved that chemical and botanical morphology are not one an 
the same, at least the two are very intimately correlated. =} 
It has been said that many of the constituents found in plants 
are the result of destructive metabolism, and are of no iur ; 
usein the plant’s economy, but our knowledge of what i 
tute plastic and waste products is by no means settled, and 
should we be forced to accept the conclusion that some piat" | 
are of no use to the plant, yet it is a significant fact that cerat 
cell-tissues or organs secrete or excrete chemical comp 
peculiar to them, and which are only to be found in one% 
or in species closely allied to it. confined 
Broadly speaking, the study of plant-life cannot be : 
within the limits of the vegetable-cell, since its radiations 
gous series in plants; by the study of embryology *~ 
3 that alantoin occurs in animal- and plant-life, also gl at i 
inosite are found in both kingdoms, and the secretion ER 
plant-leaves is a fluid chemically like the animal gastric ju 
_M. Leo Errera, in a recent paper on a fundamental € 
_ of equilibrium of living cells, calls attention to the thin and 
commeien of plant- as well as animal-cells at the moment 
formation, and their tendency to assume a form which, 
_ Same conditions, an imponderable lamina of liquid we 
~ And he attributes to this fact their adaptability and ye 
o : * Comp. Rend., t. xiii., 1886, p. 822. ; 
