30 THE CRUCIFER FAMILY. 
usually simple, and rough with short hairs. Radical leaves spreading, 
obovate or oblong, slightly toothed; stem-leaves generally erect, 
oblong, or lanceolate, entire or nearly so, all, or at least the upper ones, 
clasping the stem by short auricles. Flowers small and white, Pods 
slender, 1 to 2 inches long, erect and crowded in a long raceme, Seeds 
without any wing. A. sagittata, DC., Zurritis hirsuta, Linn. 
On walls, banks, and rocks, common in the greater part of Europe 
and Russian Asia, but not in high northern latitudes. Not an abundant 
plant in Britain, although occurring in numerous localities, even in 
the north of Scotland. 1. summer [Var. glabrata, Syme, has nearly 
elabrous leaves. | 
4.{[A. alpina, Linn. (fig. 59). Alpine R.—Very near A. hirsuta, but 
less stiff; stem-leaves coarsely toothed, flowers larger and fruiting — 
racemes shorter, with more spreading pods. 
A native of the Alps and Arctic regions of Europe, Asia, and North | 
America, lately discovered by Mr. H. C. Hart on the Cuchullin mountains 
in Skye. ] | 
5. A. ciliata, Br. (fig. 60). Fringed R.—Very near A. hirsuta, but 
not above 6 inches high ; the stem usually glabrous, and the leaves only 
fringed with a few stiff hairs on their edge, the upper ones rounded at 
the base and not auricled. The flowers are rather larger, and the pods 
less erect. 
In stony and rocky places, in the mountains of central Europe. In 
Britain only at a few stations in 8. Wales and the west coast of 
Ireland. Fl. summer. There is some doubt whether the British and 
the Continental plants are the same, but probably both are mere 
varieties of the common 4A. hirsuta. . 
6. A. Thaliana, Linn. (fig. 61). Zhale #., Thalecress, Wallcress.—A 
slender, erect, branching annual, usually about 6 inches high, but 
sometimes attaining a foot, clothed with short, spreading stiff hairs, 
or sometimes nearly glabrous. Leaves mostly radical and spreading, 
oblong, with a few coarse teeth, from 4 to 1 inch long. Stem-leaves few, 
small, and sessile. Flowers small and white. Pods on spreading 
pedicles, in slender racemes, narrow linear, varying from 4 to 5 inches 
long to twice that length. Seeds small, the two rows blended into 
one; the cotyledons placed obliquely, so that the radicle is almost 
incumbent on the back of one of them. Stsymbrium Thaliana, Hook. 
On old walls, dry banks, and stony waste places throughout Europe 
and Russian Asia, extending into northern America. Frequent in 
Britain. Fl. early spring, and occasionally also in summer and autumn. 
On account of the position of the radicle this species is referred by 
some to Sisymbrium, with which it has little else in common. 
7. A. stricta, Huds. (fig. 62). Bristol Rockeress.—A perennial, but 
probably of few years’ duration, resembling in some respects the A. 
petrea. Radical leaves in a small spreading tuft, pinnately lobed, and 
hispid with stiff hairs. Stems about 6 inches high, erect, nearly 
simple, with a very few small leaves narrowed at the base. Petals 
narrow and erect. Pods erect, about an inch long. 
The Continental distribution of this species is uncertain, as the name 
is often given to plants quite different frem ours; but it appears to be 
a native of limestone rocks in the mountains of western Hurope. In 
Britain only on St. Vincent’s rocks, near: Bristol, where it is becoming 
