VOL. XX. (i) 
FLOWERING OF PLANTS 
IS 
wet.” Miss Jekyll in her book Old West Surrey, speaking of the 
wryneck, quotes : “ When we hears that, we very soon thinks 
about rining (barking) the oaks.” 
There is something delightfully picturesque in the thought 
of man thus helped and guided in some of his most vital opera- 
tions by the proceedings of the world of plants and animals, to 
whom that hard task-master Natural Selection has taught so 
much. 
I have gone through Blomefield’s Calendar, recording for 
each species the number of days between the earliest and 
latest known dates of flowering. Thus the Mezereon did not 
flower earlier than January nth or later than February 2nd ; 
this means that the date of flowering may, as far as we know, 
vary to the extent of twenty-three days. 
If we look at the recorded dates for all flowers appearing in 
February, we find great irregularity. Thus Daphne laureola 
has a range of 22 days, whereas for Vinca minor the figure is 
114. The average for February is 75.6, that for March is 55.6, 
for May 29.5, July 29.6. These figures suggest that the range 
of dates of flowering diminishes as the temperature becomes less 
variable. But the variation in summer temperature, though 
small relatively to the same factor in the cold months, may 
nevertheless be sufficient to affect the flowering habit. But 
there must be many factors in the problem of which we know 
nothing. It is a curious little fact that the summer range 
should be roughly one month. 
Let us now consider my observations for 1917 as compared 
with Blomefield’s record of the mean date of flowering of the 
same species. 
The most striking feature occurs at the beginning of April, 
when Blomefield’s observations are on the whole markedly 
earlier than my record of corresponding facts. Of those noted 
by me as flowering in April, one should have flowered in January, 
four in February, five in March, six considerably earlier in April, 
and two slightly earlier in that month. 
In May Blomefield’s dates are still mainly earlier than mine, 
in spite of the fact that in this month the temperature was above 
the normal. In June, on the whole (though with much 
