pallidiora, laxe tomeatosa. Stamina erecta, sepalis multo breviora: Filamenta filiform!»: Anther# lineares,
flavte. Pistilla staminum longitudine: Styli graciles, longi, valde sericeo-hirsuti.
T-t.\b- On the west side of the Rocky Mountains, near the sources of the Columbia. Douglas.—This
beautiful species of Clematis is quite unlike any hitherto described; and I am anxious it should bear the
name of its zealous and meritorious discoverer. In general habit it accords with De Candolle’s 5th Div. of
« fflammul#” (including C.integrifolia, ochroleuca, and ovata,) but in all the species of that groupe the leaves
are simple, whereas here they are deeply divided, almost as in Pceonia tenuifolia. The primary divisions, indeed,
might rather be called pinnate than pinnatifid, but the lowermost leaves, which are simply pinnatifid,
with much broader segments than the rest, show their true nature. In the middle and uppermost leaves, the
primary divisions, or pinnae, are in two opposite pairs; so close to the base of the rachis, and so much
larger than the rest, that, at first sight, they give the appearance of verticillate leaves.
3. C. verticillaris ; pedunculis unifloris, foliis quaternatim verticillatis ternatis foliolis
cordato-acuminatis sublobatis integerrimis serratisque, petalis acutis.—De Cand. Syst.
Veget. v. 1. p. 166. Prodr. v. 1. p. 10.—Atragene Americana. Sims, in Bot. Mag. t. 887.
Pursh, FI. Am, v. 2. p. 384. Bigel. FI. Bost. ed. 2. p. 219.
fi. foliolis obtuse serratis.— C. obliqua. Douglas, MSS.
Foliola lateralia semper obliqua, magis minusve obtuse serrata vel plerumque omnino integerrima, parce
pilosa. Pedunculus e basi pedunculorum vetustorum egrediens, foliis duobus stipatus. Flos cernuus. Se-
pdla magna, corollina, ovato-lanceolate, acuta, cserulea vel purpurea, extus magis minusve pilosa. Petala
calyce duplo triplove breviora, lineai-ia, quo interiora eo magis distincto antherifera.
Hab. In woods in the central districts, as far north as lat. 54°, ascending the elevated valleys on the eastern
declivity of the Rocky Mountains in that latitude. Dr. Richardson. Drummond. At Cape Mendocina, on
the N.W. coast, in lat. 40°: plentiful. Douglas.—Nearly allied to Clematis {Atragene, Linn.) alpina, but
differing, in its acute petals, and in the far smaller.and never sharply serrated leaves. This beautiful plant
does not appear to be found farther north than lat. 54°, nor south of Pennsylvania, on the east side. It is
not included in Elliott’s Sketch.
2. t h a l ic t r u m .
Jnvolucrum sub flore nullum. Pet. nulla. Carpella sicca in caudas non desipentia, nunc
stipitata, nunc longitudinaliter striato-sulcata.—Herbas perennes ; caulis annuus; Acres
corymbosi-paniculati aut subracemosi, herbacei, albi vel flavi. DC.
1. T. clavatum; hermaphroditum, filamentis cl'avatis, antheris ellipticis muticis, car-
pellis inflatis stipitatis laevibus oblongis stylo longioribus, foliolis subrotundis crenato-
lobatis glabris subtus glaucis.—De Cand. Syst. Veget. v. 1. p. 171. De Less. Ic. v. 1. t. 6.
De Cand. Prodr. v. 1. p. 11.
Tota planta glabra, pedalis. ad sesquipedalem. Caulis nitidus, ramosus. Folia triternate, foliolis (nostris
examplaribus) magnitudine T. dioici, et iis similibus, subtus valde glaucis. Stipell# nullse. Panicula sub-
pauciflora, laxa, pedicellis longis. Flores erecti. Stamim pauca, brevia, perianthii longitudine. Filamenta
supeme insigniter dilatata. Antherae breves, elliptic«, muticse. Pistilla ,8-10 in smgulo flore. Germen
ovatum, stipitatum, gibbum, lseve, demum inflatum, in stylo, germine, £ breviore attenuatum.
Hab Found only on Portage La Loche, a height of land composed of sandhills, lying in lat. 57°, and
separating the waters flowing to Hudson’s Bay from those falling into the Arctic Sea. Dr. Richardson.—
This species of Thalictrum, which seems to have been found only in one spot by our American travellers,
exactly accords with the figure of T. clavatum, in De Lessert’s leones, in every particular, except that the
leaves in our plant are smaller, which may arise from accidental causes, and that its styles are rather shorter.
Both my specimens and the individual figured by De Lessert, have perfect, not monoecious, flowers, as
described by De Candolle; and it would seem that Michaux’s specimens (it does not appear in what part of
America they were gathered,) are the authority both for De Lessert’s figure and De Candolle’s description.
I have not seen ripe carpels, nor has De Lessert represented them. Is it not possible that thé present may
be a state of T. dioicum ? (with which, in habit and foliage, the plant entirely agrees,) having pistils and
stamens on the same flower, both of which are differently modified from what we find in the dioecious state.
2. T. dioicum; floribus dioicis, filamentis filiformibus, foliolis subrotundis crenato-
lobatis glabris subtüs glaucis.—Linn. Sp. PI. p . 768. Pursh, FI. Am. v. 2. p. 388, Bigel.
FI. Bost. ed. 2. p . 220. Elliott, Carol, v. 2. p. 50. De Less. Ic. v. 1 .1. 8. De Cand. Prodr.
v. 1. p . 12.—T. lasvigatum. Mich. Am. v. 1. p . 322.
Caulis pedalis nunc bipedalis. Folia fere omnino ut in T. clavato, submollia, membranacea. Panicula
terminalis, magis minusvè longa. Stamina numerosa, filamentis filiformibus, antheris linearibus mucronatis.
Germen oblongo-ovatum, hinc intus planum, stylo stigmateque lineari duplo brevius. Stigma deciduum.
Fructus semi-ovatus, sulcatus, stylo persistente acuminatus.
Hab. Grassy banks of rivers; most abundant in the central limestone districts, from Canada to the banks
of the Mackenzie River, in lat. 67°. Dr. Richardson. Found also on the eastern base of the Rocky Mountains.
Drummond; and on the banks of the Columbia. {Mr. Garry.) Not found on the barren grounds,
nor on naked alpine situations.—An abundant plant, and, as far as I can judge from the numerous specimens
in the different collections, very constant to its character. Dr. Richardson’s T.corynellum in FrankL 1st
Journ. ed. 2. includes specimens of T dioicum and T. Comuti of this work: some of the former having
been overlooked among his specimens.
3. T. purpurascens; “ floribus dioicis monoicisve, filamentis filiformibus coloratis, folio-
rum segmentis suborbiculatis grosse dentatis glabris subtus glaucis, panicula contracta
subapliylla.” DC.—-Linn. Sp. PI. p. 169. Pursh, PI. Am, v. 2. p . 389. De Cand. Prodr.
v. 1. p . .12.
Hab. Canada. Linn.—This is probably only T. dioicum, with purplish flowers.
4. T. Comuti; floribus plerumque dioicis, filamentis subclavatis, antheris ellipticis
sublinëaribusve, foliolis subrotundo-obovatis oblongisve trilobis subtus glaucis nervis
vix prominentibus, carpellis ovato-oblongis, stigmate filiformi marginibus membranaceis.
(Tab. II.)
*. antheris lineari-oblongis.—T. Comuti. Linn. Sp. PI. p. 768. Pursh, FI. Am. v. 2. p.
388.—T. revolutum. De Cand. Syst. Veget. v. 1. p. 173.? Prodr. v. l. p . 12.? Elliott,
Carol, v. 2. p. 49.—T. Canadense. “ Comuti, Canada 186. t. 187.”
/3. antheris ellipticis.—T. pubescens. Pursh, FI. Am. v. 2. p . 388. Nutt. N. Am. Gen.
v. 2. p. 21.—T. corynellum. De Cand. Syst. Veget. v. 1. p . 172. Prodr. v. 1. p . 12. Rich,
in FrankL ls£ Journ. ed. 2. App. p. 21.
Caulis 3-4-pedalis, ramosus. Foliola forma mire variant in iisdem examplaribus, nunc ovata, nunc cordate,
et non raio obovato-oblonga vel cuneata, majuscula, trilobate, lobis plerumque acutis; superne intense
viridia, subtus pallidiora, glauca, glabra vel pubescentia. Panicula composite, foliosa. Stamimm filamenta
magis minusve elongate et clavata: antherce ellipticae, oblongm vel lineari-oblonga;. Pistilla numerosa in
singulo flore foemineo : germen nigrum, oblongo-ovatum, subgibbosum; stylus breviusculus; stigma longum,
lineare, margine utrinque membranaceum,. dilatatum. Fructum maturum non vidi.
Hab. Banks of rivers as far north as lat. 56°, in woody districts the whole breadth of the continent,
excluding the barren grounds and alpine tracts—Variable as this plant assuredly is, it may be at once