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it is probable that in a general way northern plants, and spring- 
blossoming plants, are related; and that the causes which tend to 
produce the one, when exerted in a different way, also tend to 
produce the other. The result finds its expression in the Botanies, 
when the distribution of a spring-flowering plant is given as 
being from a certain line northward, instead of southward, as 
is apt to be the case of true summer-flowering plants. 
It is very natural that the flower.buds intended to blossom 
the succeeding spring should occasionally be prematurely devel- 
oped by the warm weather towards autumn. Autumn flower- 
ing of fall plants has been mentioned so frequently by writers 
that I will give only two cases in point: Cornus Canadensis, 
found in flower at Rutland, Vermont, late in August; and Fra- 
garia Virginiana, also seen in blossom, on Mt. Greylock, near 
North Adams, Massachuetts. 
This, however, is a different phenomenon from the fall-flower- 
ing of spring flowers which keep up a desultory sort of flowering 
all summer, but are apt to blossom again freely in the fall; as is 
the case with dandelions, chickweed, and similar plants. In the 
case of the fall- flowering of violets, the fall blossoms are sim- 
ply the more mature and typical continuation of a long series 
of flowers, which during the summer are represented only by 
stunted cleistogamous forms. Then again, many spring-flower- 
ing annuals are apt, in the fall, to be again brought to the point 
of flowering by very favorable weather, from seed which in the 
ordinary course of nature would have developed to the point of 
a flowering plant first, the succeeding spring. The cases of the 
Cornel and Strawberry referred to above, are however, instances 
of premature development of a flower bud which was already 
in existence in accordance with the ordinary laws of nature. 
Having shown that the development of the flower buds of 
spring plants, during the previous summer and autumn, was 
quite a common occurrence, it becomes important now to inves- 
tigate the life history of certain early spring-blossoming peren- 
nials, such as Dentaria laciniata, Erigenta bulbosa, and Isopyrum 
biternatum, which, “althou gh flowering early in the season, do not 
seem to have the flower buds even started in the winter buds so 
far examined. 
