thefe feed-veffels are included in the feminal valves, the ftraps
are rolled round the placenta, in two oppofite fpiral directions,
as is expreffed at C, where they are beginning to unroll
j at D, they are reprefented as farther difengaged ; at F,
they are quite expanded ; and at G , the elaftic force of the
filaments being quite exhaufted, they are at reft. This unrolling
of the ftraps or filaments, however, is not gradual, as
I have reprefented it, but performed in an inftant, by a fudden
jerk ; by which the feeds are thrown off with force, and
committed to the air, where they float innumerable. What
is their ufe ? Certainly they are produced for other purpofes
befides the propagation of the fpecies ; every perfe£l feed
fpike produces millions of thefe, and yet the plant is propo-
gated by the root; nay, fo rarely do the feeds anfwer the
purpofe of propogation, in this family, that I could never
yet difcover a feedling plant of any one of the fpecies.
The fame obfervation holds good, in refpe£l to all the
other Ferns, and to the Fungi ; the multitude of feeds produced
by an Agaric or a Boletus, is innumerable ! is aftomlh-
ing ! yet not one of ten thoufand anfwers the purpofe of propogation.
Is not the Air we breathe charged with them all
the declining part of the year } Do we not receive them into
our Lungs with every breath we draw Whence proceed the
Quinfies,