1895.] Deviation in Development Due to the use of Unripe Seeds. 809 
percentage of germination according to degree of maturity 
(see table I). In experiments performed by myself in 1889 to- 
I.—GERMINATION OF SPRUCE SEEDS AT DIFFERENT STAGES OF 
MATURITY. 
Experiment conducted ey Nobbe. 
Spruce seed, gathered July 15, gave O per cent i perhiinations: 
Spruce seed, gathered Aug. 1, gave 40.8 per cent germinations. 
Spruce seed, gathered Aug. 15, gave 61.2 per cent germinations. 
Spruce seed, gathered Sept. 1, gave 75.3 per cent germinations. 
Spruce seed, gathered Sept. 15, gave 71.6 per cent germinations. 
Sprnce seed, gathered Oct. 1, gave 84 5 per cent germinations. 
Spruce seed, gathered Nov. 1, gave 88.2 per cent germinations. 
mato seed from green and ripe fruit of the previous season, 
tested in April in the laboratory, gave 60 per cent germination 
for the immature seed against 100 per cent for the fully ma- 
ture. Considerable other data are on record, all going to show 
that seeds are more certain to germinate the nearer they ap- 
proach to maturity, or conversely, the more immature the seed, 
the less number of chances for its germination. 
The internal examination of the seed to determine the actual 
stage of development, in connection with such studies, has been 
rarely attempted. Seyffert and Cohn agree, however, that with 
- such seeds as peas, beans, lentils, canna and evening primrose, 
the embryo must be sufficiently formed to be detected with a 
hand lens, in order that the seed should be capable of growth. 
If the embryo is watery and unformed, according to these ob- 
servers, the seed will not germinate. 
Probably most of us would at first think, as Cohn” did, that 
“it is a curious circumstance in this connection, that while in 
the ripening of the seed innumerable stages are run through, 
passing one into the other without interruption, in germina- 
tion, which is as it were a function of maturity, no transition 
exists. For evidently a seed can only either germinate or not 
21 Es zeigt sich hierbei der eigenthiimliche — dass während bei der 
Reife der Same unzählige, ohne Unterbrechung in einander übergehende Stufen 
durchläuft, bei der Keimfihigkeit. die gleichsam Fusion der Reife ist; kein 
Uebergang existirt. Denn offenbar kann ein Same nur a R, oder 
nicht; ein drittes giebt es nicht. Cohn, Flora, xxxii (1849), p 
