1915] ROSE—DELAYED GERMINATION 429 
It is plain that treatment with the machine increased germi- 
nation considerably in the case not only of legumes, but also of 
snapdragon, Delphinium, sweet marjoram, Ipomoea, okra, and 
lettuce. 
TABLE I 
GERMINATION OF SEED TREATED WITH MACHINE 
| 
GERMINATION 
Kinp oF sexo aero eee 
z Untreated Treated 
RS cg tok ou eek ee eee Io 51 99 
MUN tc cd ak ee tee oe ce Io 74 94 
oscere eternnnylia ook veo ey ie 30 3 73 
Hossiaea scolopendria. .............-.<. 30 II 52 
}uanthus Dampieri. os) sec. es 10 ° 80 
White clover....... peas EUS. eek to 7° 94 
eipuimum chinense. 3.2, . 2... se. 30 74 96 
wwenta erictiolia’ 0 ck ood ok 30 2 77 
Bree RS Nee aa go ° 70 
Ipomoea (average of 3 spp.)........-.-. 10 34 | 71 
Lathyrus (average of 3 vars.).........-. 14 63 93 
| ce (av _ € Of TT vars. 3, ay oe 12 55 83 
arene tidriitere rk ee a 30 54 96 
Mustard irs Ot 2 wars) 6 oe. 14 20 69 
Oe ea ee 30 34 79 
cap peas (average x 2 vars. )- ee: 10 62 87 
Swee peas (average of § vars.).......... 14 | 7° 99 
Plath trilobatunk 66s Fel 30 13 64 
tom then 4g) ee oe eo OT Ee ee eee! 30 6 23 
Kites ee eeu eo ee an eas 10 77 92 
RNCTAIE RCT ee ee | 40.7 83.7 
Vieleats due to treatment: ioe heres o.- cates eas eva 43-7 
It is not strictly correct, however, to call lettuce seeds hard- 
coated. That their germination is improved by treatment with the 
machine shows delay to be due to coat restrictions. The coat 
restrictions are removed also by soaking in water for 24 hours, 
hence it is likely that delay is caused by a reduction in rate of 
water absorption rather than by lack of oxygen. Whatever be 
the character of the seed coat, or coats, which interferes with 
germination, it disappears as the seed grows older. These points 
are well illustrated by table II. The data here presented support 
the statement made by various seedsmen, that two or three-year-_ 
old lettuce seed gives better germination than fresh. How this 
condition comes about is not known, but it probably depends on 
