MacDouGaL: SomME CORRELATIONS OF LEAVES 505. 
growing near by were also available for comparison. The earlier 
part of the season was one of extreme drought. During the 
period of fifty-two days between April 16, a week before the be- 
ginning of the test, a total precipitation of only 1 cm. was recorded. 
It was noted that the scales and stipules were of longer duration 
and presented the appearance of increased superficial extension 
upon the delaminated branches within a fortnight after beginning 
the tests. The development of leaves and buds appeared to have 
almost ceased and an anatomical examination was made June 3-10: 
with the following results : 
The greatest length made by branches which had been defoliated 
from the beginning was 18 cm., while a length of 25 and 30 cm. 
was found in normal branches; 18—20 leaves had been formed 
on defoliated branches and but 14 or 15 on normal ones. The 
basal internodes of the twigs showed but little difference in length 
in the two instances, being as much as 2 cm., although less in some 
cases. The internodes formed later in the season on the normal 
twigs attained a length of as much as 3.5 cm. in some instances, 
while those of the defoliated twigs varied from 1.5 cm. to one 
third that length. Consequently the defoliated twigs were closely 
crowded at the terminal part with scales and stipules. This. 
crowding effect was accentuated by the fact that one or two small 
leaves were thrust out of the axillary buds, although no general 
activity of the bud was exhibited. In contrast with the behavior 
of Acer, it could not be made out that any extra number of lateral 
buds on the older parts of the branches below had been induced 
to awaken. 
The correlative alterations in the stipules were very marked 
and consisted in changes in form, size, position, structure and 
period of endurance. Normal stipules of the cherry are thin- 
membranaceous, and generally of a reddish tinge containing almost 
no chlorophyl. These stipules are usually short-lived and fall off 
in such manner that on the above date they could be found only 
on two or three leaves on the terminal portions of twigs. The 
stipules on twigs on which the leaves had been dissected were 
both broader and longer, offering a superficial expansion of about 
five times the normal (see f. 7). The maximum measurements 
were but little greater than those of normal stipules formed earlier 
