52 FLOWERS OF GARDEN AND GREENHOUSE 
seed-vessel throughout the Order Crucifers, though varying in size and 
shape. Fig 1 is a section through the flower, showing arrangement of 
organs. Fig. 2, the two-celled ovary and stigmas; 3, the ripened siliqua 
or pod opening by two valves to discharge the red seeds; 4, a seed, 
natural size, and the same enlarged. 
ROCK-CRESS 
Natural Order Crucifers. Genus Aubrietia 
Aubrietia (named after M. Aubriet, a French botanical artist). A genus 
of half a dozen species of dwarf evergreen trailing plants, with hairy, 
entire or toothed leaves, and few, comparatively large purple or violet 
flowers. They are natives of the Mediterranean region. 
There is little of historical interest concerning this 
0ry ’ genus. The British gardener knew* it not until 1710, when 
Aubrietia deltoidea was introduced from Naples. Its very low stature 
and neat habit made it welcome as a rock-plant, for bordering and for 
carpet-bedding, and under cultivation it has produced a number of 
varieties and several hybrids. Respecting certain of these forms there 
is considerable disparity of opinion as to whether they should be ranked 
as separate species or as varieties of deltoidea. 
species and Aubrietia deltoidea (shaped like the Greek letter A)- 
varieties. 4 inches; the name is supposed to refer to the shape of the 
leaves, but it is a misnomer: they are nearer oval, with one or two teeth 
on either side and rough with branched hairs. The outer sepals have 
saccate bases as in Cheiranthus, but they are green; the petals are 
purple, the yellow stamens contrasting prettily with them; flowers, 
March to May. 
A. purpurea (purple), 4 inches, is somewhat larger of stature and 
has larger, deeper flowers; stems more leafy, and leaves broader with 
more teeth; whole plant more erect; March to May. 
The principal varieties and hybrids are the following:— 
BovganvUlei (Bonganville’s), very dwarf, 
owing to shortness of flower-stalks; 
flowers light violet-purple, petals over¬ 
lapping. 
Campbelli (Campbell’s), also known as 
Hendersoni; larger, deep violet - blue 
andiflora (large flowefed), 1 
