266 BOTANICAL GAZETTE [APRIL 
comparison of determinations of absorption by Verbascum Thapsus 
seeds in light (series 2) and in darkness (series 4) indicates the same 
general relations. The data for the other seeds show similar 
results. From this experiment it appears that light is not necessary 
for the absorption of sufficient water for germination. 
Injection of seeds with water 
De Vries (8), having abandoned variation of temperatures, 
high temperatures (40-50° C.), and other treatments of seeds of 
Oenothera biennis as means of securing complete germination, 
injected soaked seeds with water under pressure of 6-8 atmospheres, 
after which he frequently secured germination of 100 per cent. The 
TABLE XI 
/DARKNESS| THEN IN |DARKNESS| THEN IN 
SEED: FOR LIGHT FOR FOR LIGHT FOR UNTREATED 
sd 17 Days | 7 DAYS is DAYS | 7 DAYS 
(a) (db) Light Darkness 
Verbascum Thapsus...... I 4 ° 24 81 ° 
mucne Canta cys: 6 Io 8 12 61 21 
othera biennis........ 8 43° 5 55 33 
RUMEL CLISOUS 3 oe 5 8 Il 56 71 3r 
Nicotiana Tabacum....... 4 54 5 60 83 ° 
seeds (table XI, a) accordingly were soaked overnight at a tempera- 
ture of 25-28° C., wrapped in filter paper, placed in water, exhausted 
of the air in their intercellular spaces by reducing the atmospheric 
pressure to 20 mm. for 1 hour, and then subjected to hydrogen 
gas pressure of 575-675 pounds per square inch for 24 hours. The 
seeds were then placed to germinate in darkness under the usual 
conditions. A second lot (6) was treated in the same way except 
that it was subjected to a pressure of 500-650 pounds per square 
inch for 48 hours. Both lots were germinated at room temperature. 
Evidently injection with water does not increase the germination of 
seeds of Oenothera biennis, Nicotiana Tabacum, Daucus Carota, or 
Rumex crispus in darkness. When the seeds are subsequently 
exposed to light, they germinate in one or both tests. These results 
confirm the conclusion arrived at in the weighing experiments, that 
impermeability to water is not the limiting factor in light germi- 
