CRUCIFEROUS PLANTS. 99 
It is unnecessary to adduce any descriptive details, as such can 
be found in special works ; but it is desirable to give an outline 
of the general characteristics, by which any cruciferous plant can 
be recognised and thus be placed into its proper ordinal position. 
Crucifere: Sepals free, always four, in somewhat unequal 
pairs, mostly with their margins overlapping in bud; the outer 
pair opposite to the placentas ; the inner pair usually more pro- 
tracted at the base. Petals four, rarely two or none, deciduous. 
Stamens six, rarely fewer, only in one known instance numerous. 
Anther-cells slit along the inner face. Stigmas two, generally 
confluent. Fruit often deciduously two-valved, and longitudinally 
two-celled. Seeds fixed to the intervalvular narrow placentas. 
Albumen none or very rarely present. Embryo oily, variously 
- curved, hardly ever straight; radicle very often adscendent. 
Herbaceous or not frequently half-woody plants, of volatile 
acridity and limpid sap. Leaves mostly scattered, at the root 
often crowded. Flowers with rare exceptions in racemes. 
Stipules and bracteoles none. 
Erysimum received its generic name from its resemblance to 
Sisymbrium, to which Theophrastos applied already that appella- 
tion before the Christian era, and of which three species also occur in 
Victorian territory, particularly in the North-western desert-regions, 
where the majority of our Crucifere are to be found. LE. lasio- 
carpum was specifically so named on account of its hairy fruits. 
From the Wimmera to the Murray-River may be met sparsely in 
early spring a small stemless annual herb, with deeply lobed leaves 
and with fruits crowded at the roots ; this is the G'eococcus pusillus, 
remarkable as the name implies for usually burying its fruit 
during the maturation-process in the sand, into which many of it 
fully descend. This and a Vigna lanceolata (a bean-bearing 
plant of Queensland) furnish the only instances among Australian 
plants of this curious economy of growth, of which however the 
well known Arachis hypogaea, (the pea-nut or ground-nut of 
Brazil) gives a familiar example. Our common Wéi/d Cress 
(Lepidium ruderale) is identical with that of the northern hemi- 
sphere. Soalso the Sea-Rocket (Cakile maritima) and the ordinary 
yellow-flowered Watercress (Nasturtium terrestre) do not differ 
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