100 CRUCIFEROUS PLANTS. 
from the plants of Britain and many other countries. Cakile 
must be sought near highwater-mark on sand-coasts, where it is 
the only cruciferous plant, able to exist under such circumstances. 
It is very conspicuous with its succulent leaves and comparatively 
large purplish flowers; it is also very remarkable among plants of 
its order in its fruits, consisting of two parts, separated by trans- 
verse articulation, both one-celled and indehiscent, the lower joint 
gradually dilated upwards with a pendent seed; the upper joint 
attenuated towards the apex with an erect seed. The name Cakile 
occurred first in the writings of the ancient Arabic Physician 
Serapion, and seems to signify the use of this plant as an appli- 
cation to tumors. The appellation Nasturtium for Watercresses 
emanates already from the writings of Plinius, changed from 
Nasitortium, on account of the pungency of a cress-like plant, 
to which it was first applied. Lepidium received its name also 
from-the same ancient naturalist in allusion to its scale-shaped 
fruits. 
At the very outset of examining a cruciferous plant, the 
position of the radicle towards the cotyledons must be ascertained, 
and also at once must be enquired, whether the cotyledons are 
straight or folded, as on these criterions the distribution of the 
numerous genera into tribes largely depends. When the seeds 
are very minute, the dissection is facilicated, as also in many 
other subtle analyses, by mollifying them in boiling water. It 
will then more easily be seen, after removal of the outer seed- 
pellicle, whether the edges of the cotyledons are turned to the 
(accumbent) radicle, or whether the latter (¢ncumbent) faces the 
sides of the cotyledons ; or in other words whether the position 
of the radicle towards the cotyledons is marginal or dorsal ; the 
presence or absence of flexures of the cotyledons becomes also 
best apparent in soaked seeds. In this manner is also easily 
observed, that the embryo (cotyledons and radicle) is not sur- 
rounded by any albuminous separate mass in seeds of cruciferous 
plants, unless in very rare instances. 
To the series of orders, which contains the Crucifere, belong 
also Papaveraceze and Capparidez, each of which represented 
only by a solitary genus and species in this colony. 
