from the British American Flora.—The flowers of this are not known, and it may be considered doubtful if
any true Alyssum is found in North America.
12. DRABA. Linn.
Silicula sessilis. ovalis aut oblonga, valvis planis convexisve. Semina plurima immar-
ginata. Calyx sequalis. Petala integra. Stamina omnia edentulai DC.
* Permnes. Scapiplerumque aphyM.
1. D. algida; flaccida, scapis brevibus nudis patenti-pilosis, foliis oblongis planis caly-
cibusque pilosis, pilis plerumque simplicibus, siliculis subcorymbosis ellipticis glabnsj
stylo perbrevi, (floribus flavisJ.JK“ Adams in Bert. Fisch.” De Cand. Prodr. v. 1. p. 167.
Cham, et Schlecht. in Linntea, v- 1- P- 21-
Y. brachycarpa, DC.; silienlis brevioribns. De Cand. Prodr. 1. c.
3. breviscapa ; scapo foliis glabriusculis immerso.
Han Sea coast between the Mackenzie and Coppermine Rivers. Dr. Michardson. J. In deep sand.—I
have not had any opportunity of seeing authentic specimens of D. algida: but its characters agree with
those of our present plant, and, according to De Candolle and Chamisso, it must be very nearly allied to
D alpina; so much so, that the latter author doubts if what he describes as the y. braAycarpa be not a
dwarf state of alpina. De Candolle says that it is known from that species and all the yeUow-dowered
ones by its simple not branched hairs. In onr plant, however, it must be confessed there are a few branched
hairs mixed with the more abundant simple ones. The roots are long and slender, , the lower part of the
numerous, dichotomously divided branches shaggy with the remains of former yearn’ leaves: the perfect
leaves as well as the stem, are soft and flaccid, oblongo-spathulate, hairy principally at the margin: the
scapes scarcely twice the length of the leaves, even when bearing fruit, hairy or glabrous, as is tins calyx,
even on the same plant. Pedicels always glabrous. Petals twice the length of the calyx, obovate.
Capsules elliptical or elliptic-oblong, shortly oval in y , and sometimes also in a. Style short, but distinct.
Stigma oblong, lobed. In S. the flower is quite immersed among the leaves.
2. D. alpina; subrigida; scapis nudis pubescenti-hirsuti* foliis lanceolatis planis pilis
plerumque ramosis, petalis calycem plusquam duplo longioribus (plerumque flavis) sillcuiis
subcorymbosis oblongo-ellipticis, stylo brevi.—L im . Sp. P I P- 896. PI. Dan. f . 56. (foliis
nimis latis.) Wahl. Lapp. v. 1. p. 173. t. 11. ƒ 4. (sed stigmate breviore quam in nostr.
exempl.) Br. in Parry’s 1st Voy. App. p. 265. Rich, in FranU. 1st Jtmm. ed. 2. Aqrp. p.
27. Hook, in Parry's 2d Voy. App. p. 385.
». siliculis glabris. “ Herb. Linn.” Br. 1. c.
fi. siliculis pilosis. Br. 1. c.—D. alpina. Br. Spitzb. PI. in Scoresby's Arctic Meg.
floribus albis.
Han. From 1st. 60° on the Mountains, to the shores of the Arctic Sea, and on the islands adjacent, where
it principally abounds, extending westward to Kotzebue’s Sound, (Captain Beechers CoUectum), and the
Island of St Lawrence, (Chamisso) : found by all the Arctic Travellers. S. Only on tho sea
of the Mackenzie River. Captain Sir J. FrrnMm and Captain Back—De Candolle says of this, that the
flowers are smaller than those of D. ahoides. It is not so in onr specimens! they are remarkable for their
size and generally flue yellow colour, rarely white, or very pale yellow. The calyx, pedoncle, andscape,
are liable to vary in their degree of hairiness. This does not appear to grow farther south than « .6 0 , nor
did Mr. Drummond or Mr. Douglas And it at the greatest elevation of the Rocky Mountains, where t h ^
crossed the chain. In that alpine and southern latitude, the species seems to be replaced by the following
very closely allied one.
3. D. glacialis ; scapo nudo stellatim pubescente vel glabro, foliis lineari-lanceolatis
rigidis integris stellato-pubescentibus, petalis (flavis) calycem duplo longioribus, siliculis
longe racemosis (an semper?) oblongo-ovatis, stylo brevi.—“Adams, Mém. Soc. Nat. Mosq.
5. p. 106.” De Cand. Prodr. v. 1. p. 167. Graham in Edin. Phil. Journ. 1829. p . 183.
ct. scapis pedicellis siliculisque glabris, floribus pallidis.
/3. scapis pedicellisque pubescentibus, siliculis glabris.
y. scapis pedicellis siliculisque valde pubescenti-hirsutis.
$. minor, scapis numerosis pedicellisque glabris, floribus pallidioribus.
i. minor, scapis pedicellisque glabris, floribus intense luteis.
H ab. Rocks on the loftiest of the Rocky Mountains, between lat. 52° and 57°. Drummond. Rare on
the shores of the Arctic Sea. Dr. Richardson.—Closely allied, as De Candolle observes, to the two preceding
species; differing from both in its longer, narrower, and more rigid leaves, which are clothed with short,
and generally dense, stellated pubescence, and furnished, on the underside especially, with a strong and
prominent midrib. In consequence of their firm texture, the former years’ leaves remain attached at the
base, when they lose their pubescence, becoming bleached and glossy, so as greatly to resemble D. aizoides,
from which again this species differs by its pubescent, never ciliated, leaves, and far shorter, though yet very
evident, style to the capsule.
4. D. oligosperma; scapo nudo subpubescente, foliis erectis rigidis subnitidis linearibus
ciliatis versus apicem praecipue utrinque stellatim pubescentibus, petalis (albis) calycem
pilosiusculum duplo excedentibus, siliculis pubescentibus longe racemosis ellipticis basi
apieeque acutis 4—8 spermis, stylo sub \ breviore.
Radix perennis, tenuis, sublouge descendeus, superne multiceps. Caules breves, unciam-2-uncias longi,
ramosi, inferne foliorum vetustorum vestigiis obsiti. Folia erecta, linearia, obtusiuscula, iuferne subattenuata,
rigida, nitida, utrinque sed versus apicem praecipue stellatim pubescentia, margine ciliata, pilis simplicibus vel
ramosis. Scapi terminales, nudi vel raro versus basin unifoliati, rigidiusculi, digitales, pedicellique
minute stellatim pubescentes. Flores etiam racemosi. Calyx glaber, vel paree pilosus, jnlis patentibus.
Petala alba, obovata, basi in unguem attenuata. PistiUum: Germen oblongum, utrinque atteuuatum, stylo
subtriplo breviore terminatum : Stigma integrum. Siliculce in racemum laxum, duas uncias longse, elliptic«,
planse, utrinque acutae, pube brevi sparsa tectse, loculis 2-3, rarius 4-spermis. Stylus evidentissimus, silicula
subquadruplo brevior, stigmate integro capitato. Pedicelli fructiferi siliculis paulo longiores.
Hab. Summit of a limestone hill, Mackenzie River, lat. 68°. Dr. Richardson.—Unwilling as I am to
increase the number of species in this most difficult genus, I yet venture to do so in the case of the present
individual, which was found in considerable abundance and perfection, though only in one spot, bearing
both flowers and fruit. Although in the three preceding species, if such they may be called, De Candolle
designates the style as brevissimus, it can only be so in reference to that of his preceding groupe, the
Aizopsis family; for the style is assuredly much longer than in any of the following species with naked
scapes. Now, in that particular, and in the rigid foliage and generally short stellated pubescence, it approaches
D. glacialis, whilst its white flowers and general habit assimilate it with the D. hirta tribe. It is remarkable
for having the lower pedicels of the raceme bearing fruit, whilst the upper ones have perfect flowers. The
seeds are mostly two or three in each cell.
5. D. pauciflora ; scapis aphyllis pedicellisque pilosis, foliis lanceolatis integerrimis pilis
furcatis simplicibusque, petalis (flavis) spathulatis calycem hirsutum vix superantibus,
ovariis glabris. Br. in Parry's 1st Voy. App. p . cclxvi. Hook, in Parry's 2d Voy. App.
p. 385.
H ab. Melville Island. Capt. Sabine. Barrow River. Capt. Sir E. Parry. “ Dubia species, alpina
G 2