13? 



itig 1 seed, having a membranous pericarpium, and terminated by an indurated style, which 

 finally curls back from the base upwards, carrying the pericarpium along with it. Seeds soli- 

 tary, pendulous, without albumen. Embryo curved ; radicle pointing to the base of the cell ; 

 cotyledons foliaccous, convolute, and plaited. — Herbaceous plants or shrubs. Stems tumid, and 

 separate at the joints. Leaves either opposite or alternate; in the latter case opposite the pe- 

 duncles. 



Affinities. In many points nearly related to Oxalideae, Balsamineae, and 

 Trop.eoleae, with which they are by some botanists associated. They are, 

 however, distinguished by the peculiar dehiscence of the fruit, their stems with 

 tumid joints, their convolute plaited cotyledons, and habit. In the arrangement 

 of their carpella about an elevated axis, they agree with all those orders for- 

 merly comprehended under the common name of Rutacere, from which the 

 length of that axis, and many other characters, distinguish them. Their ana- 

 logy with Vites is pointed out in speaking of that order. In many respects they 

 border close upon Malvaceae. 



Geography. Very unequally distributed over various parts of the world. 

 A great proportion is found in the Cape of Good Hope, chiefly of the genus Pe- 

 largonium ; Erodium and Geranium are principally natives of Europe, North 

 America, and Northern Asia, and Rhyncotheca of South America. It is re- 

 markable that Pelargonium is found in New Holland. 



Properties. An astringent principle and an aromatic or resinous flavour 

 are the characteristics of this order. The stem of Geranium spinosum burns 

 like a torch, and gives out an agreeable odour. The root of Geranium macu- 

 Iatum is considered a valuable astringent in North America, where it is some- 

 times called Alum root. Barton, 1. 155. In North Wales Geranium Rober- 

 tianum has acquired celebrity as a remedy for nephritic complaints. Ibid. 

 Some of the Pelargoniums are acidulous, but this genus is chiefly known as 

 an object of garden culture, for which its great beauty, and the facility with 

 which the species or supposed species intermix, render it well adapted. 



Examples. Geranium, Monsonia, Erodium. 



CXXIII. OXALIDEAE. The Woodsorrel Tribe. 



Oxalidejb, Dec. Prodr. 1. 689. (1824) ; Lindl. Synops. 59. (1829.) 



Diagnosis. Polypetalous dicotyledons, with definite hypogynous stamens 

 distinct except at the base, concrete carpella, an ovarium of several cells with 

 the placentae in the axis, an imbricated calyx, symmetrical flowers, indefinite 

 exalbuminous seeds with a straight embryo, and compound leaves. 



Anomalies. 



Essential Character.— Sepals 5, sometimes slightly cohering at the base, persistent, 

 pqual. Petals 5, hypoyynous, equal, unguiculate, with a spirally-twisted aestivation. Stamens 

 10, usually more or less monadelphous, "those opposite the petals forming an inner series, and 

 longer than the others; anthers 2- celled, innate. Ovarium with 5 angles and 5 cells; styles 

 5, filiform; stigmata capitate or somewhat bifid. Fruit capsular, membranous, with 5 cells, 

 and from 5 to 10 valves. Seeds few, fixed to the axis, enclosed within a fleshy integument, 

 which curls back at the maturity of the fruit, and expels the seeds with elasticity. Albumen 

 between cartilaginous and fleshy. Embryo the length of the albumen .with a long radicle 

 pointing to the hilum, and foliaceous cotyledons.— Herbaceous plants, under-shrnbs or trees. 

 Leaves alternate, compound, sometimes simple by abortion, very seldom opposite or somewhat 

 whorled. 



Affinities. Formerly included in Geraniaces, from which, in the judg- 

 ment of many, they are not sufficiently distinct. According to M. Decandolle 



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