I I
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The manner in which the feeds of the Horfetails are dif-
charged is beautiful, and well deferves our regard. The
laborious and ingenuous Hedwig has well illuftrated this particular,
by a number of figures, in his Theoria PI. Crypt.
Tab. I , 2. And I have found the truth of his Obfervations
by examining the fame fubje£ls, under the firft magnifier of
C u ff’ s Compound Microfcope, as now fold by Nairn and
Blount, in London 5 my figures, however, vary a little from
thofe of Hedwig.
In the annexed Plate, A , is a fingle fhield feparated from
the fiower fpike, and magnified with its curved fupport, and
its fix feminal valves unopened. Thefe valves open by a longitudinal
future from top to bottom, on the inner fide, and
copiouily difcharge a foft downy powder, which when newly
fallen or ihook out may, through a moderate fpy-glafs, be
feen to ikip and leap about as if alive j after the difcharge of
this powder the feminal valves or capfules remain for fome
time in an horizontal direftion, empty and dry, as is ex-
prefled at B ; where the underfide of the ihield and the infide
of the valves are reprefented.
The feparate feed-veifels, if fuch we may call them, con-
fift of an oval placenta, and four fpoon-ihaped filaments or
ftraps J to thefe laft the feeds immediately adhere. While
thefe