
65 
EXPERIMENT I. 
Average temp. 52.1° F. Extremes 48.5° and 55.5° F. 
Hours. 
First 
seed Half Last Per cent 
sprouted. sprouted, sprouted. germinated. 
MUON Ovaries Jct. el oUt 141 171 209 100 
CNA SO FRAC en ne 140 140 185 100 
Oy ah a or 195 259 281 100 
RP EMMUT MOEN Bl otic wlan wens oe a w= 161 209 250 100 
PTL teh oy gi Ee aig ae 140 150 209 100 
EXPERIMENT II, 
Average temp. 48.2° F. Extremes 45.3° and 50.7°. 
Tv Tes Le 216 276 396 100 
Vc RAS Ce 168 192 252 100 
aye) OL ee th 288 348 408 100 
Dee mee Vai: So 228 312 408 100 
eR OME AY fe Shp hs eo we Sg 5 ow 228 276 396 100 
‘T'wice each day the seeds were carefully examined, and those which 
showed the acrospire just broken through the pellicle of the seed 
were removed. ‘The lowest temperature maintained during any one 
period during which germinative changes appeared in Exp. I, was 
54.5° and all the form species showed germination progress under 
this temperature. In Experiment II, we were more successful in 
maintaining low temperatures. The dents germinated during in- 
tervals when the highest temperature was 47.6° and the lowest 
46.5°; the flints when the temperature varied from 46.5° to 47.8°; 
the sweets when 48.5° was the highest point reached; the softs when 
48° was the highest; the pops below 47. 8. 
Experiment ale was commenced Jan. 7, 1885, with one variety of 
each of the form-species, with the hope of maintaining a tempera- 
ture constantly below 47°. The results are given below in some- 
what more detail than in the preceding trials. The apparatus was 
opened at noon each day, and rise of temperature during the exam- 
ination was guarded against by the use of snow. ‘T’he duration of 
the trial 1008 hours. 
EXPERIMENT III. 
First germination. 
Variety Extremes Hours. Total Per cent. 
and of 
per cent, left Lowest temp. at which 
Form species. temp. germin- unger- germination took place 
ated. minated. between two countings, 
and the hour. 
**Chester Co. 
mammoth” Dent 48.5°—47.8° 264 100 0 45.1° bet. 264—288th hr. 
‘““Waushakum ” 
Flint 48.5°—47.8° 336 92 8 47.1° bet.884—482nd hr. 
*“Pearl’’ Pop 43.5°—47.8° 336 80 20 43.2° bet. 456—480th hr. 
‘“Puscarora”’ Soft 43.5°—49.6° 408 84. 12 438.2° bet. 456—480th hr. 
- “Stowell’s Ever- 
green” Sweet 41.7°—49.6° 504 84 12 45.3° bet.528—552nd hr. 
It seemed probable therefore that germination could take place 
somewhere between 43° and 45°. 
To test this question, a new apparatus was prepared, more com- 
lete than was used in the preliminary tests, and within which it was 
ped a constant temperature, within one or two degrees, could be 
3) 
