|Brassicacae (crucifers, cabbage family)
Above and left: Garlic Mustard, Alliaria
Oilseed rape, Brassica napus.
Brassicacae usually have four separate sepals and
four separate petals. There are usually 6 stamens: 4
longer inner stamens and 2 outer shorter stamens,
although the latter are sometimes lost. The ovary is
usually two-celled, though each cell may contain
many ovules in some species. A single style bears
Capsella bursa-pastoris, the Shepherd's Purse.
Garlic Mustard, Alliaria petiolata.
Above and below: The characteristic 'purse-shaped' fruit capsule which gives the Shepherd's
Purse its common name. Some forms of this species are diploid ( with two sets of 8
chromosomes each, 2n = 16) whereas others are tetraploid (4n = 32). The diploids tend to
have smaller fruit and more dissected and more acutely tipped leaves.
Below: Stellate hairs on the pedicels.
Above: each fruit dehisces by shedding two valves, releasing the orange-brown seeds. The dividing membrane (septum or replum), to which the
two valves were joined, remains, outlined by veins. The protuberances projecting from the rim veins are the placentas, as can be seen below, in
which some of the seeds are still in situ with attached placentas.
This type of short pod (length less than three times the width) is called a silicle.