

67 
The conclusion, is therefore unquestionable, that Adams Early 
Dent, and Chester County Mammoth Dent Maize germinated in 233 
hours at an average temperature of about 43.4°, with extremes of 
14.5° and 43.7°, and the figures for the first germinations in the 
various trials for these dents are:— 
Exp. Average Highest No. of hours required 
temperature. temp. for germination. 
is 52.1 55.5 140 
Uy, 48,2 50.7 168 
II1. 45.5 47.8 264 
Lv 43.4 43.7 233 
We note here that fewer hours were required for germination un- 
der the lowest temperature, than under a higher temperature. This 
possibly comes from the individual variability of the kernels, as in 
Exp. II for illustration. out of 25 seed of Tuscarora corn, 2 ger- 
minated on the 408th hour, and 1 on the 1008th hour, with 3 appar- 
ently sound yet not germinated after this interval; or possibly from 
the low temperature maintained in Exp. III just preceding the first 
germination. 
The individual variation between seed, as shown by these germi- 
nation trials, are very great, and hence we should not expect very ex- 
act correspondences in the number of hours required for the appear- 
ance of the acrospire at different temperatures, one trial giving dif- 
ferent figures from another, unless large numbers of seed be used. 
It is also difficult to examine our seed without change of tempera- 
ture occuring during the exposure to examination, and hence we 
must satisfy ourselves with examination as distant as will satisfy the 
conditions of the trial. In these later trials, we formed a judgment 
from earlier experiments as to about when the first germination was 
to be expected. At this period and after this, daily or not more fre- 
quently, the apparatus was opened, the rise of temperature restrained 
by the use of water at 36°, and each seed hastily examined, account 
only being made of the fact of, and not the numbers of, germina- 
tion. We thus have Experiment V. 
EXPERIMENT V. 
Number of hours to first germination noted. 
43.7° F, 

Extreme temperatures 41.5° 
{ Adams Early Dent 233 
) Chester Co. Mammoth Dent =. 233 
1 Waushakum Flint 381 
Kight-rowed White Flint 331 
{ Tuscarora Soft 348 
/ Zuni Blue Soft 431 
( White Pearl Pop 378 
Amber Rice Pop 378 
| Dwarf Golden Pop 498 
1 Stowell’s Evergreen Sweet 452 
Narragansett Sweet 498 
