THE ELEMENTS OF ORGANIC EVOLUTION. 97 
are for the most part those of minor importance, the 
superficial traits of the species rather than the deep- 
seated qualities of the group, But these are none the 
less real, and to this series of influences much of the 
variety of the life of the globe must be attributed. 
The survival of the existing, which is the basis of 
most of the distinctions between one species and another, 
is not less real than the survival of the 
fittest. In making up the fauna or flora 
of any region, those creatures actually 
present must leave their qualities as an inheritance. If 
they can not maintain themselves, their type passes 
away as unfit. If they maintain themselves in isolation, 
their characters become persistent as those of the new 
species. 
Still other factors in organic evolution may be more 
or less clearly defined, either in connection with those 
above mentioned or as fundamentally distinct. 
One of these is the following: The transmission of 
characters of the parent as distinct from proper hered- 
ity. A starved hill of corn means ill- 
nourished grains. The plants produced 
from ill-nourished seeds may be stunted 
by lack of vitality or lack of starch without any change 
or deficiency in the germ itself. In like manner feeble 
children may owe their traits to the temporary illnesses 
of a strong mother. A sound mind demands a sound 
body, and a sound body is necessary to well-nourished 
offspring. With the characters of the germ cell these 
conditions have nothing to do, and their homologue is 
found in such defects as insufficiency of milk. 
VIII. Lxheritance of Acquired Characters—The in- 
heritance of acquired characters mentioned above, a 
process of transmission possibly different from germ 
heredity, has been lately the subject of much discussion. 
Survival of the 
existing. 
Nutrition in 
transmission. 
