Draba.] VI. CRUCIFERZ. 41 
Crucifer, is still much shorter, in proportion to its width, than in the 
shortest Arabis. 
Flowers yellow (stiff tufted perennial) . : ; ; ; . 1. D. aizoides. 
Flowers white. . 
Biennials or perennials. Pedicels short and stiff. 
Stem with a few leaves, the radical ones spreading 3. D. incana. 
Stem almost leafless, the radical ones tufted . ; ' . 2D: hirta. 
Annuals. Pedicels slender, spreading. 
Stem dwarf, erect, leafless. Petals deeply divided . 5, D. verna. 
Steam weak, ascending, leafy. Petalsentire . ; 4. D. muralis. 
1. D. aizoides, Linn. (fig. 89). Yellow D,—Stock perennial and 
branched, covered with closely packed leaves, forming dense tufts of 
2 or 3 inches diameter. The leaves 3 or 4 lines long, sessile, linear, 
of a bright green, edged with stiff white hairs, Peduncles leafless, 1 
to 4 or even 5 inches high, bearing a few rather large yellow flowers. 
Pods about 4 inches long, glabrous or slightly hairy, with a rather long 
style; the valves more convex than in the rest of the genus, 
In clefts of rocks, and stony places, in the mountain districts of 
central and southern Europe. Long cultivated in our rock-gardens, it 
_has established itself in considerable abundance on rocks and old walls 
about Penard Castle, near Swansea. 1. spring. 
2. D. hirta, Linn. (fig. 90). Rock D.—Stock shortly tufted and 
perennial, but not of long duration. Leaves crowded, 3 to d or 6 lines 
long, narrow, oblong, or lanceolate, entire or shghtly toothed, with a few 
stiff, simple or stellate hairs. Peduncles usually 1 or 2 inches, and 
leafless ; in luxuriant specimens twice as long, with 1 or 2 small ovate 
leaves. Flowers few and small, but larger than in D. incana. Pods 2 
to 3 lines long, on short stiff pedicels, usually slightly hoary with a 
few very minute hairs. D. rupestris, Br. 
In the mountains of the northern or Arctic regions of Europe, Asia, 
and North America, Rare on some of the higher mountain summits of 
Scotland and North-west Ireland. fl. July. The specimens with 
slightly hoary pods (as are the Scotch ones) are by some distinguished, 
under the name of D. rupestris, from the original D. hirta of Linnzeus 
(not found in Britain), in which they are almost or quite glabrous. 
8. D.incana, Linn. (fig. 91). Hoary D.—Nearly allied to D. hirta, 
but very different in appearance. Often only a biennial, with the 
radical leaves spreading, and seldom forming branched tufts ; the whole 
plant hoary with short, simple, and stellate hairs. Stems erect, 6 inches 
high or more, with several small, sessile, oblong, or lanceolate leaves. 
Flowers small, and white. Pods 3 to 5 lines long, on short stiff pedicels, 
glabrous, or sprinkled with a few stellate hairs; the valves flat, or the 
whole pod slightly twisted. D. confusa, Ehrh. 
In rocky situations, in northern and Arctic Europe and Asia, far more 
common than D. hirta, and descending to lower elevations. Frequent 
in the Scotch Highlands, and extending into northern England, North 
Wales, and Ireland, where it also occurs on maritime sandhills. 7. 
summer. 
4, D. muralis, Linn. (fig. 92). Wall D.—A slender, erect, but weak 
annual, from a few inches to a foot high, simple or slightly branched, 
green, but rough with short hairs. Radical leaves spreading, ovate or 
oblong, toothed, 4 to 1 inch long. Stem-leaves smaller, ovate, clasping 
the stem by their cordate or auricled base. Petals white, entire, and 
