aE eT Te RE 
1892.1 Relations of Fall to Spring Blossoming Plants. q 
mediate summer months, the development of the fall flower- 
ing species from those blooming in spring, in the manner 
described above, is very likely to be the case. As a matter 
of fact, most fall blossoming plants belong to the first class, 
The ideal time for the flowering season of plants is in late 
spring and early summer. In the struggle in the race for 
~existence two tendencies set in. The one is to secure ad- 
vantage over surrounding plants by increasing in size and thus 
securing more light, air and room for the development of their 
own flowers. This tends to result in late summer and in au- 
tumn‘flowering plants. The other is to gain advantage over 
other plants by the earlier blossoming of their flowers, or by 
blossoming before the foliage of the trees overhead, or that 
of the surrounding plants can cut off the light or otherwise 
interfere with their development. This tends to produce 
spring flowering plants. Autumn blossoming plants, which 
are the result of the extreme development of the latter prin- 
flowering seasons of plants, that this freak of fall flowering 
has become a permanent one for a greater number of plants 
than botanists usually suppose, and that there should be rec- 
ognized a distinct division of fall flowering plants eit near- 
est relatives are with those that blossom in the spri 
If the principle that spring flowering plants are ides 
from summer flowering plants by the reduction of their inter- 
nodes, be kept in view, it is evident that this result might be 
attained through the struggle for light and room zx sztu. The 
same result would be attained if summer plants should migrate 
temporarily toward the north, or up mountain sides, since the 
shortening of the period favorable for vegetation might ope-— 
rate in reducing the number of internodes and in hastening 
the perfection of the flowering buds, while after these altera- 
tions had become permanent, a return to more congenial 
climates would favor earlier, possibly spring blossoming. — Es- 
sentially the same conditions would exist 7” sztu, if the colder 
climate of a glacial period should come down from the north. 
The reduction of the period favorable for floral development 
would again operate in reducing internodes and in hastening 
the development of floral buds. ,The retreat of glacial cli- 
mate would favor earlier blossoming, in many cases spring 
blossoming. Plants which were spring blossomers in the far 
