127 
most advisable to keep the order near Illecebracesc with which it accords in its 
syncarpous unilocular, often 3-valved fruit, and scale-like leaves. 
Geography. Exclusively confined to the northern hemisphere, and even 
to its eastern half, that is, to the old world, on which the species extend as far as 
the Cape de Verds. They usually grow by the sea-side, but occasionally by the 
edges of rivers and torrents. The maximum of species and of individuals also 
is found in the basin of the Mediterranean. The order appears bounded on 
the south by the 8® or 9° parallel of N. lat., and on the north by that of 50° 
and 55° in Siberia, Germany, and England. Ehrenb. 
Properties. The bark is slightly bitter, astringent, and probably tonic. 
T. gallica and africana are remarkable for the quantity of sulphate of soda 
which their ashes contain, DC. Ehrenberg found that the Manna of Mount 
Sinai is produced by a variety of Tamarix gallica. This substance, being ana- 
■ lysed by Mitscherlich, was found to contain no crystallisable Mannite, but to 
consist wholly of pure mucilaginous sugar. Ann. des Sc. 1. c. The galls of 
T. indica, dioica, Furas and orientalis are- highly astringent, and are used both 
in medicine and in dyeing. Royle. 
GENERA. 
Tamarix, L. Bronnia, H. B. K. 
Myricaria, Desv. Trichaurus, Arn. 
Order XCVII. ILLECEBRACEtE. The Knot-Grass Tribe. 
Herniari^e, Cat. Hort. Par. (1777). — Illecebre^e, R. Brown Prodromus, 413. (1810) ; 
Lindl. Synops. 60. (1829). — Paronychie.e, Jug. St. HU. M^m. Plac. lib. p. 56. 
(1815) ; Juss. Mtm. Mas. 1. 387. (1815) ; DC. Prodr. 3. 365. (1828) ; Memoirs sur 
les Paronych. (1829) ; Bartl. Ord. Nat. p. 301. (1830). 
Essential Character. — Sepals 5, seldom 3 or 4, sometimes distinct, sometimes 
cohering more or less. Petals minute, inserted upon the calyx between the lobes, occa- 
sionally wanting. Stamens perigynous exactly opposite the sepals, if equal to them in 
number, sometimes fewer by abortion, sometimes more numerous ; filaments distinct ; an- 
thers 2 celled. Ovary 1 -celled, rarely 3-celled, with 1 or more ovules, superior ; styles 2-5, 
either distinct or partially combined. Fruit small, dry, 1 -celled, rarely 3-celled, either 
indehiscent, or opening with 3 valves. Seeds either numerous, upon a free central pla- 
centa, or solitary and pendulous from a funiculus originating in the base of the cavity of 
the fruit ; albumen farinaceous ; embryo lying on one side of the albumen, curved more or 
less, with the radicle always pointing to the hilum ; cotyledons small. — Herbaceous or half- 
shrubby branching plants, with opposite or alternate, often fascicled, sessile, entire leaves, 
and scarious stipules. Flowers minute, with scarious bracts. 
Affinities. Very near Portulacacese, Amarantacese, and Alsinacese, from 
which they are distinguished with difficulty. By excluding Scleranthaceae, 
which I consider, with Brown, a distinct order, their scarious stipules will dis- 
tinguish them from the Silenacese and Alsinacese ; and there is scarcely any 
other character that wiU ; for there are Alsinacese that have perigynous sta- 
mens, as Larbrea and Honkenya, and Illecebracese which have hypogynous 
ones, as Polycarpsea, Stipulicida, and Ortegia. From Portulacacese they are 
scarcely to be known with absolute certainty, except by the position of the 
stamens before the sepals instead of the petals, and the number of the sepals. 
With Crassulacese, particularly Tillsea, they agree very much in habit, but 
their concrete carpels will always distinguish them. De Candolle comprehends 
in the order various plants which have not stipules ; but as the latter organs 
seem to be an essential part of the character, I should exclude his Queriacese, 
and Minuartiese, which will be reduced to Alsinacese. According to Cambes- 
