( 252 `) 
XXIV. Of the Developement of t ie seminal Germ. By the Rev. 
Patrick Keith, F. L.S. 
Read November 16, 1813. 
No phænomenon observable in the process of germination has. 
excited so much wonder, and remained at the same time so totally 
inexplicable, as that of the invincible tendency of the radicle and 
plumelet to insinuate themselves respectively into the soil and 
atmosphere, independent and in despite of all accidental obsta- 
cles that may happen to be thrown in their way. 
If a seed or nut of any sort is placed in the proper soil with 
the apex of the radicle pointing downwards, the radicle as it 
elongates will descend in a perpendicular direction and fix itself 
in the earth; and the plumelet issuing from the opposite extre- 
mity of the seed will assume a vertical direction and ascend into 
the air. This is the natural order of the developement of the semi- 
nal germ ; and from the relative situation of its respective parts 
its developement does not seem to be at all surprising. But the 
circumstance exciting our surprise is, that the radicle and plume- 
let will still continue to effect their developement invariably in 
the same manner, whatever may have been the original position 
in which the seed was deposited in the soil. For, if its position 
shall happen to have been accidentally inverted, so as that the 
radicle shall be uppermost and the plumelet undermost, the 
former will then bend itself down tillit gets a hold of the soil, 
and 
