CVIII. DATISCE^J. 455 



winged on the 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. FRUIT 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. EMBRYO 

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

 petal. 



PKINCIPAL GENERA. 



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



The affinities of Begoniacece are very uncertain, and their place has therefore been repeatedly 

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

 and Datiscece. The latter have, like Begoniacece, diclinous flowers, a polyandrous androecium with extrorse 

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

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

 anatropous ovules, a capsular fruit, sub-exalbuminous seeds, a straight cylindric 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 unknown 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. Begonia malabarica and tubei-osa [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 are ornamental hothouse plants, as B. incarnata, semperflorens, manicata, 

 coccinea, Rex, fuchsioides, cinnabanna, heracleifolia, argyrostigma, 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 Hillebrandia, a Begoniaceous genus, in the Sandwich Islands, has enabled Professor 

 Oliver to settle the affinities of Begoniacece, which are undoubtedly close to Saxifragece. Another recently 

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

 nulate perianth and definite stamens.] 



CVIII. DATISCECE. 



(DATISCE^B, Presl. DATISCACEJE, Lindl.) 



HERBS or TREES. LEAVES alternate, imparipinnate or palminerved and sub- 

 inequilateral, exstipulate. FLOWERS usually dioscious, sometimes 5 or polygamous, 

 greenish, small, in a panicle or spicate raceme. FLOWERS $ : CALYX 3-9-tid. 

 COROLLA 0. STAMENS 3-15, inserted on the calyx ; anthers 2-celled, dorsifixed, 

 dehiscence longitudinal, extrorse. FLOWERS ? and $ : CALYX with a superior 3-8- 

 toothed limb. COROLLA 0. STAMENS in the $ equal and alternate to the calycinal 



