34 
more nor less than a mere thesis which is worshipped by those 
whom scruples and doubt do not enthrall, and who, in their san- 
guinism, accept that as truth which in their estimation is desirable. 
The phylogenetic method of procedure has some scientific value. 
as is evidenced from the paleontologic data of general evolution. 
It is necessary in all cases to add to these phylogenetic construc- 
tions certain hypothetical assumptions so as to form a rationally 
appearing chain of evidence. To exclude hypothetical assump- 
tions from the domains of science is impossible; they are neces- 
sary in botany as well as in physics and chemistry. It is the object 
of science to point out what constitutes positive facts and what is 
only relatively true or hypothetical. If we ignore this distinction 
we become unscientific. As an illustration, may be mentioned 
the premature fruit of hyper-Darwinism, which has such a delete- 
rious influence in the realms of natural science. 
The parts of a plant stand to each other in the relation of a 
morphological equilibrium. This equilibrium is more or less labile, 
but it may acquire a high degree of stability. Ina given indi- 
vidual the greatest morphological lability exists in the embryo. 
It tends toward continual change. Among the higher plants (ex., 
a tree), there are as many points of labile equilibrium as there are 
meristematic areas. A mature leaf has reached the state of stable 
equilibrium ; it changes neither in size or form. Neoformations 
may however be induced by special stimuli, producing a state of 
temporary lability. 
All species are in a state of morphological lability as long as 
they are variable. Struggle for existence and other causes finally 
produced stability of form. : 
At this point the author’s arguments become peculiarly weak 
and antiquated. He assumes that the majority of plants and ani- 
mals now living have reached.a state of morphological stability. 
Many stable forms have gone out of existence because they could 
not adapt themselves to the changes in environment. As evi- 
dence for the existence of such stability the author states that our ~ 
most common plants of cultivation have not undergone any ap- | 
preciable change within thousands of years. Man is cited to il- 
lustrate stability in the animal kingdom. Homer is compared 
with moderns to prove that the psychological peculiarities have 4 
