26 Schively—Recent Observations on 
occurred under its ordinary conditions. The form of the 
legume, the size and shape of the seed, and also the histolog- 
ical peculiarities remained unaffected. 
To recapitulate—from the above statements, there seems 
to exist a relationship between the age of the legume selected, 
and the extent of modifications to be expected as a result 
of the action of the changed conditions. Those legumes sub- 
jected to new environmental conditions, while the tissues were 
yet plastic though quite undifferentiated, responded readily in 
all respects. The result was remarkable, both morphologically 
and histologically, for the legume as well as its contents. When, 
however, the legume was allowed to develop for a time under 
its ordinary surroundings, then the changes were found to 
vary in proportion to the state of development which had 
been attained before the new conditions were given an oppor- 
tunity to act. 
In this connection it may be well to point out that subter- 
ranean flowers or their young legumes, if kept growing in the 
air, will produce legumes with contents which are typically 
aerial, but such pods are always small, and contain only one 
seed. These statements are based upon experiments made 
with certain shoots which grew from the axils of the simple 
leaves (first pair of green leaves) of a plant. These shoots 
normally trail on the surface of the ground, and give rise to 
flowers which produce subterranean legumes. Certain of 
them were tied so that they were compelled to grow upward 
to the height of four or five feet. Upon the secondary 
branches which were thus forced to mature fruit above ground, 
were borne legumes of the character described. 
These experiments are striking illustrations of the remark- 
able influence exerted by environmental conditions upon por- 
tions of Amphicarpea possessing absolutely the same structure 
in the young state. When one is exposed to light, and the 
other to darkness, totally different morphological results are 
obtained. Doubtless there are other factors which are quite 
