162 ENGLISH BOTANY. 
15 leaflets, which are lanceolate or elliptical, often cut or lobed. 
Petioles of the stem leaves expanded at the base, with long narrow 
acute ciliated auricles embracing the stem. Petals erect, oblanceo- 
late, once and a half as long as the sepals, but most frequently 
abortive. Pod linear, terminated by a style whose length is about 
equal to the breadth of the pod. 
In shady woods and on moist rocks. Rare. It has been found 
in the counties of Surrey, Somerset, Gloucester, Glamorgan, Wor- 
cester, Warwick, Shropshire, Montgomery, Denbigh, Derby, and 
York. It has been reported from some of the more northern 
counties, and from the banks of the Doune in Ayrshire, and the 
Falls of the Clyde in Lanarkshire. 
England, Scotland? Biennial or Annual. Summer. 
Tap-root sending up a single stem, sometimes with the inter- 
vention of a short rootstock clothed with root fibres. Stem erect, 
simple or branched, 1 to 2 feet high. Stem leaves very numerous, 
with the divisions closer and more nearly at right angles to the 
petiole than in any other of the British species of Cardamine. 
Leaflets + to 14 inch long, acute, generally cleft into 2 or 3 lobes 
towards the base. Petals very rarely present. Fruit pedicels about 
1 inch long. Pods # to 1 inch in length. Style rather slender. 
Plant nearly glabrous. 
This species cannot be confounded with any of the others if 
attention be paid to the curious auricles at the base of the leaf stalks. 
The leaves are not truly pinnate, but only pinnatipartite ; for all the 
leaflets are joined by a narrow strip or wing, which runs down each 
side of the common petiole; this strip is expanded at the base, and 
from the expansion narrow lobes are given off, which embrace the 
stem, so that the petiole is sagittate at the base. 
Impatient-podded Ladies’ Smock. 
French, Cardamine Impatiente. 
The common name of this species arises from the fact that the pods are peculiarly 
sensitive to the stimulus of heat ; on warm sunny days they may be seen and heard 
exploding with a contractile force, which after expelling the seeds causes the valves 
of the pod to curl up in a singular manner. 
GENUS XIT—ARABIS. Linn. 
Sepals sub-erect, equal, or the lateral ones slightly gibbous at 
the base. Petals equal, entire, with moderately long or short claws. 
Filaments without wings or teeth. Pod linear, cylindrical or sub- 
quadrangular, compressed; valves with a dorsal nerve, or several 
