
874 THE AMERICAN NATURALIST. [VoL. XXXVI. 
Weak individuals are more apt to show earlier stages than 
are more vigorous plants. They represent plants which are 
less accelerated in their development, not attaining the charac- 
ters usual in plants of their age and other conditions. This is 
true whether the whole is weak or whether the growth comes 
from adventitious or weaker buds. The same is true of plants 
injured by outside agencies; for example, when the leaves are 
stripped by insects and a later growth put out from the weaker 
buds, before undeveloped. 
Soil and moisture conditions come into play here. The poor 
sandy soil and lack of moisture mentioned in the first two exam- 
ples given, shows its effect by producing weak individuals. 
Plants in poor, dry soil often repeat stages not seen in strong, 
vigorous plants in other places. 
In studying these localized stages, especially in the early 
spring growth of herbaceous plants, some things must be espe- 
cially looked out for. The first leaves which appear are often 
very small and would be overlooked unless they were being 
sought for especially. Many of these plants which start very 
early in the spring adopt the rosette form, and these first early 
leaves are hidden under the later ones. These small early 
leaves are usually delicate and soon wither and drop off, espe- 
cially in rapid growth or where the rosette form is adopted. 
For these reasons many plants, even in early spring, may show 
no traces of the very early stages which they would have shown 
if examined a short time before. The surest way to find these 
first leaves is to notice where the plant is growing the year 
before and mark it in some way so that it may be looked for 
the following spring. 
As shown, seedlings may vary considerably, and also these 
stages, so that to avoid errors there is necessary a knowledge 
of the seedling or allied ones, and of ancestral forms. By 4 
close study of these localized stages and their variations — within 
limits —in many individuals, steps in the phylogeny may be 
determined which it would be impossible to fix in any other 
way. Many stages may be found in this way that in the accel- 
eration of the seedling are crowded out of the record preserved 
there. 
