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and divide variously in the inside of the pericarpium, so as to produce an appa- 

 rently 4- or 6-celled fruit out of a 1 -celled ovarium. For an explanation of 

 the manner in which this takes place, see the Botan. Register, fol. 934. From 

 Cyrtandraceae they are known by their large seeds, free from all appendage at 

 either end, by their woody placentas, and short fruit. Sesamum may be con- 

 sidered a transition from the one to the other. 



Geography. Found only within the tropics of Africa, Asia, and Ame- 

 rica. 



Properties. The leaves of Sesamum are emollient. Jts seeds contain 

 an abundance of a fixed oil, as tasteless as that of Olive od, for which it might 

 be substituted, and which is expressed in Egypt in great quantities. The 

 fresh leaf of Pedalium murex, when agitated in water, renders it mucilagi- 

 nous, in which state it is prescribed by Indian doctors in cases of dysuria and 

 gonorrhoea. 



Examples. Pedalium, Petrea, Josephinia, Martynia, Sesamum. 



CCXVI. CYRTANDRACEAE. 



Ctrtandraceje, Jack in Linn. Trans. 14. 23. (read 1822, in May). — Didymocarpeje, Don 

 in Edinb. Phil. Journ. 7. 82. (1822, July); Prodr. Fl. JS'ep. 121. (1825); Martins H. 

 R. Man. (1829). 



Diagnosis. Monopetalous dicotyledons, with a superior 1-celled or spuri- 

 ously 2-celled fruit, irregular unsymmetrical flowers, exalbuminous apterous 

 minute seeds, and membranous double placentae. 



Anomalies. 



Essential Character. — Calyx csmpanulate, 5-cleft or 5-leaved, equal. Corolla tubular, 

 irregular, 5-lobed, somewhat 2-lipped, the lobes imbricated in {estivation. Stamens 4, didy- 

 namous, of which 2 are sometimes sterile; anthers 2-celled. Ovarium superior, elongated, 

 surrounded by an annular disk, 1-cellcd, with 2 many-seeded placentae, each of which consists 

 of 2 diverging plates ; style filiform; stigma 2-lobed, or consisting of 2 plates. Fruit capsu- 

 lar or succulent ; the former siliquose and 2-valved, 1-cellcd, with double longitudinal pla- 

 centae, which often cohere, so as to give the appearance of two cells. Seeds very numerous, 

 minute, suspended, naked, or with a coma; albumen none; embryo straight, taper, orthotro- 

 pous. — Terrestrial or parasitical plants, usually herbaceous and stemless, occasionally cau- 

 lescent, and sometimes shrubby. Leaves usually opposite, one of them being dwarfed, radi- 

 cal, crenate and rugose, or smooth. Flowers umbellate, often purple or pink. 



Affinities. Very closely allied to Gesnerea, Bignoniaceaa, and Pedalinea3. 

 From the former they differ in nothing except their never having any tendency 

 to produce an inferior ovarium, their deeply-lobed placenta, their usually sili- 

 quose fruit, and the want of albumen ; agreeing entirely with them in habit. 

 From Bignoniacese they are distinguished by their herbaceous mode of growth, 

 their minute apterous seeds, 1-celled ovarium, with 2 double parietal placentae. 

 From Pedalineas they differ in nothing whatever, except their minute indefinite 

 seeds, and the membranous, not woody, texture of the fruit and placentae. 

 Sesamum forms a transition from the one order to the other, which would, per- 

 haps, be better combined. Mr. Don appears to me to have been mistaken in 

 assigning an heterotropous embryo to this tribe ; the embryo is certainly ortho- 

 tropous in Streptocarpus Rexii, with which the other genera no doubt agree. 

 Von Martius refers Ramonda hither. 



Geography. They occupy nearly the same station in the Old World as 

 Gesnereee in the New, being almost entirely confined to the tropics, unless the 



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