SYNCHRONISM IN PLANT STRUCTURES 
JOHN MUIRHEAD MACFARLANE 
Unwwersity of Pennsylvania 
In all departments of botanical inquiry it is becoming increasingly 
evident that wide observation and exactness of record are indispens- 
able, if we are to reach wide and exact conclusions as to plant life. 
So the carefully tabulated experiments of Koelreuter, Gaertner, 
Herbert, Darwin, Mendel, Vilmorin and others regarding plant cross- 
ing during the past century were the appropriate starting points for 
the more extended and exact results that are now being secured by 
plant breeders. 
The characteristic also of exact and correlated behavior on the part 
of plant organisms powerfully impressed the writer as he advanced in 
his studies of parent and hybrid types, from 1889 onward. Not the 
least striking of his results were those bearing on the relation of 
plants to environal atmospheric agents or stimuli, such as light, heat 
and water supply.t. So alike as regards constitutional vigor and 
period of blooming as for chemical nature, color, and odor of hybrids, 
it was concluded that each detail was more or less exactly between 
that of the parents; ‘‘while some vary to a greater or less degree from 
one or other parent.’’ Impressed, therefore, by such conditions, the 
writer has observed closely, during a period of twenty-five years, the 
action of those environal agents which we speak of collectively as 
climatic conditions, and the reaction of plant parts to these agents, 
with a view to determining how exactly each plant organism is corre- 
lated with its environment. This line of inquiry has received con- 
siderable attention during the past seventy-five years, under the 
term ‘‘phytophenology.”’ But the study, as well as the results se- 
cured, have been very largely ignored by botanists, or even ridiculed 
by some as yielding no conclusions of value. We would emphatically 
assert that few lines of investigation will compare with this if the 
studies are prosecuted in exact manner, and are planned so as to cover 
a definite field. 
The present communication may be suggestive in connection with 
future possible developments at such an experimental institution as 
the Brooklyn Botanic Garden, which has already had so successful a 
history under its able director. 
1 Gard. Chron. 93: 753. 1891. Trans. Roy. Soc. Edin. 37: 255. 1892. 
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