OBS. This plant has entirely the habit, and in many important points the structure of Matthiola, near which in a strictly natural method it must be placed; differing, however, in having incumbent cotyledons, and in the mucous covering of its seeds. The mucus proceeds from short tubes covering the whole surface of the testa, each containing a spiral fibre, which seems to be distinct from the membrane of the tube. A structure essentially similar is known to occur generally in several families: to what extent or in what genera of Cruciferae it may exist, I have not ascertained; it is not found, however, in those species of Matthiola which I have examined.
STURTIA.
Malvacearum genus, proximum Gossypio, affine etiam Senrae.
CHAR. GEN.--Involucrum triphyllum integerrimum. Calyx 5-dentatus, sinubus rotundatis. Petala cuneatoobovata, basi inaequilatera. Columna staminum polyandra. Ovaria 5, polysperma. Styli cohaerentes. Stigmata distincta linearia. Pericarpia . . . Semina . . .
Suffrutex orgyalis glaber; foliis petiolatis obovatis integerrimis; floribus pedunculatis solitariis.
2. STURTIA Gossypioides.
LOC. "In the beds of the creeks on the Barrier Range."--D. Sturt.
DESC. Suffrutex orgyalis glaber. Folia ramorum alterna, diametro unciali, trinervia; petiolo folium subaequanti, basi in stipulam subscariosam adnatam dilatato. Pedunculi vel potius rami floriferi suboppositifolii nec vere axillares uniflori, juxta apicem folio nano petiolato stipulis 2 distinctis stipato instructi. Involucrum foliaceum venosum, foliolis distinctis, cordatis, punctis nigricantibus glandulosis conspersis. Calyx dentibus acutis, sinubus rotundatis. Petala sesquipollicaria, uti calycis tubus glanduloso-punctata glandulis nigricantibus semi-immersis, purpurea basibus atro purpureis margine barbatis. Columna staminum e basi nuda super ad apicem usque antherifera: antheris reniformibus, loculis apice confluentibus. Pollen hispidum.
OBS. Sturtia is no doubt very nearly related to Gossypium, from which it differs in the entire and distinct leaves of its foliaceous involucrum, in the sharp teeth and broad rounded sinuses of the calyx, and possibly also in its fruit and seeds, which are, however, at present unknown. They agree in the texture and remarkable glands of the calyx, and in the structure of the columna staminum. Senra, which like Sturtia, has the foliola of its three-leaved involucrum distinct and entire, differs from it in having its calyx 5-fid with sharp sinuses, in the absence of glands, in the reduced number of stamina, and in its dispermous ovaria.
3. TRIBULUS (Hystrix) lanatus, foliis 8-10-jugis, fructibus undique tectis spinis subulatis longitudine inaequalibus: majoribus sparsis longitudinem cocci superantibus.