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T H L A S P I alpeftre.
Alpine Shepherd's Purfe.
T E T R A D T N A M I A Silkulo/a.
Gen. Char. Pouch notched, with many feeds : valves
boat-like, their keels forming the border of the
fru it: partition contrary to the valves.
Sfec. Char. Pouch inverfely heart-fbaped. Leaves
glaucous, flightly dentated, embracing the Ample
Item; radical ones on footttalks. Petals about the
length of the calyx. Seeds numerous.
S yn. Thlafpi alpeftre. Linn. Sp. PL 903.
T . montanum. Hudf. FI. An. 282. With. Pot. Arr.d74.
T . foliis Globularite. Raii Syn. 305.
( j ATHERED by Dr. Smith July 4th laft at Matlock, where it
grows abundantly on the lime-hone rocks. ’Tis doubtful whether
the root be more than biennial. Certainly Ray is miftaken
in faying it creeps. The radical leaves form a thick tuft, out
of which arifes one central item, rarely branched, which flowers
early in fummer; the lateral items are afterwards numerous,
moftly unbranched, and produce a fecond crop of flowers in
July and Auguit, as the Iberis nudicaulis. The whole herb is
glaucous, fomewhat fucculent, bitter and pungent in tafte and
fmell, yet horfes and cows feem to feed it down. The petals
are white, flightly notched, about the length of the calyx, fome-
times a little ihorter or longer. Anthers and calyx purpliih.
Seeds three or four in each cell.
Great confufion, originating with Mr. Hudfon, has arifen
about the Engliih fpecies of Thlafpi. This plant is certainly his
montanum, though the alpeftre of Linnseus, as appears from the
Herbarium and defcription of the laft mentioned author. The
Linnsean montanum differs from ours in having much larger
petals, leaves more entire, a creeping root, and only one or at
moft two feeds in each fide of the pod. Its antherae too are
yellow. We believe it to be a ftranger to our ifland. Thlafpi
alpeftre of Hudfon is really the perfoliatum of Linnaeus, as it
flood in the ill edition of Flora Anglica, and is an annual
branched plant, with dentated leaves and fmall flowers. Thofe
who like to guefs at hybrid plants might fuppofe our alpeftre
to be produced between perfoliatum and montanum; but we
would not hazard any fuch fuppofition, believing them three
naturally very diftintl fpecies, only having feveral characters
in common. The great fruitfulnefs of this fpecies is a pretty
pofitive proof againft its being a hybrid.
It is neceffary to remark that Dr. Withering, having taken
up thefe plants from Mr. Hudfon, has much confufed their
hiftory by mifapplying the accounts given of each in different
authors.