283 
average 12.2°; for the chestnut, 8° to 16° C., average 12.0°; for the 
elder, 9° to 20° C., average 13.9°; for the linden, 12° to 21° C., aver- 
age 16.4°. The mean daily maximum temperatures at the date of 
flowering for these same plants is as follows: 
Daily maxima. Daily mean. 
Plant. = SG ae —= = => 
Range. | Mean. | Range. | Mean. 
©} (6) NCEA oO! OG} 
TSR OEE) es a eee ae ie | 9__20 14,9 | 6_.14 | 9.4 
TAT cet aa eh ee Ne 13.21 16.6| 8..15 | mee 
(Nesters. meee oe eee eee ee eee eee eee 13_-25 a6 8_.16 12.0 
IDCs lies 22s Sen ene soe eee ee See ees See eee | 14..26 19.7 9_.20 13.9 
Thieves) 2S Se Ee eee ee Se See eon eee oe 17_.29 22.5 122221, 16.4 
Evidently the maximum temperatures have no clearer connection 
with the date of flowering than have the mean daily temperatures. 
The sums of temperatures from the beginning of vegetation to the 
date of flowering have also been computed by different methods and 
from different initial temperatures. The following are the results 
when the initial temperature is 0° C.: 
Sums of | Sums of 
Plant, postive | Dorit 
means. | maxima. 
aa ak = 
OOF OXOp 
INRIC ISU S eee tee ae ee ees Shr yh aa ea ee cee a erie ca Sue ence saee emcee ee Sant 359 591 
Dri st Cane eee ea, Fy miele Set 2 ns eee ee Hae Oe Wo oe 613 983 
Glos ire twee epee come tee wate! Deco. A ees, oe Co ts ON ede Loose teeeeeicsw eos 771 1,217 
DONG? «5 sonna donee k Spee Ee Be ee eee ee eae EEE le 990 1,542 
TAG So Be ee See eee CES ee Bee ee eee eee See one ot | 1277 1,938 
Here, again, as in previous cases, the relative value of the different 
methods of taking account of the temperature“is determined numer- 
ically by taking the sums of the departures from the average for the 
individual stations and years. In the present case the mean depart- 
ures as thus determined are exactly the same for both methods, so 
that four years of observations, 1880-1883, have not sufficed to decide 
as to which mode of calculation it is proper to adopt as the best. A 
similar calculation as to the amount of heat received by the lilac and 
the chestnut between the epochs of leafing and flowering leads to the 
same indecision as to the methods of calculation. The actual sums 
between the leafing and the flowering are as follows: 
Sums of | Sums of 
positive | positive 
Plant. daily | daily 
means. | maxima. 
Koh a1 
121 Cem ie Or ae eee tee Naeee Jou eek a Beak lee seen cc acearelsesees 280 | 433 
(GUNES HNGDR oS eSoSe false Bees ace Le Sie ees eee ae ee oe eS ee eee oe eee ete 250 372 
