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this evidence was wiped out, the evidence founded upon experi- 
mental zoology would not prevent William Jennings Bryan 
from expunging the teaching of evolution from American 
schools. Yet we are constantly being told that systematic work 
is only worthy of inferior intellects, and that great intellects 
turn their attention to genes or tropisms, or other superior 
subjects. 
The fact that animals have adapted themselves so wonder- 
fully to their environment, independently arriving at similar 
resuts on more than one occasion, would make one believe that 
Lowell’s famous lines: 
““Some flossifers think that a fakkilty’s granted the minnit its proved 
to be thoroughly wanted.’’ 
contain more truth than sarcasm. 
Everyone who studies the subject must admit that adapta- 
tion runs through the whole animal kingdom, and most will 
admit the frequency of homoplasmy. Nearly every zoologist 
who believes in evolution will also admit that the environment, 
in its widest sense, has been the great “potter’s thumb,’”’ mould- 
ing the organisms in form and habit. The great rift comes when 
biologists begin to discuss the manner in which this moulding 
has taken place. This has divided them into two great camps, 
one following Weismann and the other Lamarck. 
Weismann contended that the germ plasm passed from gen- 
eration to generation continuously, without a break, absolutely 
uninfluenced by the body cells or soma. Thus, any influence 
which the environment might have upon the soma could not be 
impressed upon the germ plasm. As the soma arises from the 
germ plasm at each generation, it follows that the only means 
by which heritable variation can arise is by an alteration of the 
germ plasm. While Weismann considered that the environment 
might produce modifications of the germ plasm similar to that 
produced on the soma (parallel modification) many of his fol- 
lowers do not admit this, but maintain that the germ plasm can- 
not be influenced by the environment either directly or indi- 
rectly. According to this extreme school, all variation arises 
through the mixing and sorting out of the genes during the 
mating of the sperm and egg. In this kaleidoscopic shifting of 
