CVIII. DATISCE^. 455 



winged on tlie back, rarely almost 1-celled [Mezierea) ; placentas occupying the inner 

 angle of the cells, thick, single or 2-partite, rarely semi-parietal {Mezierea) ; styles 

 usually 3, short, thick, 2-fid or pluripartite ; stigmas usually arranged on the stylary 

 branches in flexuous or spiral bands, united at the base outside ; ovules very numerous, 

 anatropous. Fbuit a capsule, rarely a berry (Mezierea). Capsule 3- (rarely 

 1-2-4-5-) celled, with loculicidal valves bearing on their centre membranous septa, 

 separated from the seminiferous axis, and coherent below and above. Seeds 

 minute, rarely funicled, obovoid, globose, ellipsoid or sub-cylindric ; testa reticulate- 

 foveolate, crustaceous ; endopleura sub-fleshy ; albumen scanty or 0. Embkto 

 straight, axile ; cotyledons very short ; radicle elongated, touching the hilum, centri- 

 petal. ' 



PEINCIPAL GENERA. 



Casparya. * Begonia. Mezierea. [Begoniella.J [Hillebrandia.J 



The affinities of Begoniacea are very uncertain, and their place has therefore heen repeatedly 

 changed. Of the families -with which they have some affinity it may be sufficient to mention CucurUtacers 

 and DatiscecB. The latter have, like Begoniacete, diclinous flowers, a polyandrous andrcecium with extrorse 

 and adnate anthers, several styles opposite to the sepals when they are isomeious, and furnished with stig- 

 matic papillse on their inner face, an inferior ovary (with parietal placentation in Mezierea), numerous 

 anatropous ovules, a capsular fruit, sub-exalbuminous seeds, a straight cylindrio axile embryo with very 

 short cotyledons ; but in Datiscece, besides the different habit, the leaves are usually imparipinnate and 

 exstipulate; the branches are not jointed and knotty; the capsule is always 1-celled, gaping at the top, &c. 

 Begoniacece inhabit almost exclusively intertropical regions ; nevertheless one species from the north of 

 China, Begonia discolor, stands our winter. They are more frequent in America than in Asia, much rarer 

 in Africa [many have of late been discovered in tropical Africa], and hitherto unknovf-n in Australia. Be- 

 goniacece contain oxalic acid, and have the properties of Sorrel, which name is given to them in the Antilles ; 

 in some species it is united with astringent and drastic substances. Several American and Asiatic species 

 are ranked among refreshing, antibilious and antiscorbutic medicines. Begmiia malabariea and tuherosa [and 

 other Indian species] are edible. The bitter root of B. tomentosa and grandiflora is considered by the Peru- 

 vians to be a powerful astringent. Some Mexican Begonias have a drastic root, used in syphilitic and scro- 

 fulous diseases. Many Begonias ai-e ornamental hothouse plants, as B. inoamata, semperflorens, manicata, 

 coecinea, Rex, fuohsioides, cinndbarina, heraoleifolia, argyfostigma, zebrina, diversifolia, &c. B. discolor is a 

 species from China, the branches of which are tinted with red above each joint, and the leaves of which 

 are green above and dark red below ; its tubers resist the most severe winters. We have noticed (page 8) 

 the vital energy of the Begonias. 



[The discovery of HiUebrandia, a Begoniaoeous genus, in the Sandwich Islands, has enabled Professor 

 Oliver to settle the affinities of Begoniaeece, which are undoubtedly close to Saxifragem. Another recently 

 discovered Begoniaceous genus (Begonielld), a native of New Granada, has a simple gamophyllous campa- 

 nulate perianth and definite stamens.] 



CVIII. DATISCEJS. 



(DATlscEiE, PresZ.— Datiscace.^, LindL) 



Heebs or TEEEs. Leaves alternate, imparipinnate or palminerved and sub- 

 inequilateral, exstipulate. Flowees usually dioecious, sometinies 5 or polygamous, 

 greenish, small, in a panicle or spicate raceme. Flowees $ : Calyx 3-9-lid. 

 Coeolla 0. Stamens 3-15, inserted on the calyx ; anthers 2-celled, dorsifixed, 

 dehiscence longitudinal, extrorse. FloweeS ? and g : Caltx with a superior 3-8- 

 toothed limb. Coeolla 0. Stamens in the g equal and alternate to the calycinal 



