XLVIII. COMMELYNE^. 869 



FLOWERS 5 . PERIANTH inferior, double. SEPALS 3. PETALS 3. STAMENS 6, 

 hypogynous, all fertile, or some sterile. OVARY superior, with 3 few-ovuled cells ; OVULES 

 orthotropous. CAPSULE with 3-2 cells, loculicidal. SEEDS albuminous. EMBRYO 

 antitropous. STEM herbaceous. LEAVES alternate. 



Succulent HERBS, annual with fibrous root, or perennial with a tuberous rhizome. 

 STEMS cylindric, knotty. LEAVES alternate, simple, entire, sheathing at the base, 

 flat or channelled, soft, nerved, sheath entire. FLOWERS 5 , or incomplete by arrest 

 of the ovary, regular or sub-irregular, usually blue, solitary, fascicled, umbellate or 

 racemed, furnished either with bracts or with spathaceous or cucullate 1-2-phyllous 

 involucres. PERIANTH double ; the outer calycine of 3 persistent sepals, the interior 

 corolline of 3 distinct sessile or clawed petals, very rarely united at the base into a 

 short tube (Cyanotis)-, caducous or marcescent, sometimes becoming fleshy after 

 flowering (Campelia), one often dissimilar or obsolete ; aestivation imbricate. STAMENS 

 6, hypogynous, opposite to the sepals and petals, sometimes in two groups (Dichori- 

 sandra), rarely 3-5 by arrest, some often antherless ; filaments filiform, usually fur- 

 nished with jointed hairs ; connective dilated ; anthers introrse, or rarely one extrorse 

 and 2 introrse in the same flower, 2-celled, cells divergent, marginal on the connec- 

 tive, very rarely adnate to its anterior face, and contiguous parallel (Dichorisandra), 

 dehiscence longitudinal, all fertile, or some sterile and deformed. OVARY free, 

 3-celled ; style simple ; stigma undivided, or obscurely 3-lobed, or sometimes con- 

 cave (Cyanotis) ; ovules inserted at the inner angle of the cells, either more than 

 two, peltate, 2-seriate on nerviform placentas; or 2 basifixed and collateral; or 

 superimposed, 1 pendulous, the other erect. CAPSULE usually accompanied by the 

 persistent perianth, 3-celled, or 2-celled by arrest, of 3-2 loculicidal semi-septiferous 

 valves. SEEDS few or solitary, ovoid, angular, peltate, or nearly square ; testa mem- 

 branous or rigid, rugose or foveolate, closely adherent to the fleshy dense albumen ; 

 hilum ventral and depressed, or at one end of the seed, and large. EMBRYO pulley- 

 shaped, sunk in a pit of the albumen, diametrically opposite to the hiluin ; radicle 

 covered by a hood (embryotegium). 



PKINCIPAL GENERA. 



* Comraelyna. * Aneilema. * Cyanotis. * Dichorisandra, 



* Tradescantia, Spironema. Campelia. Cochliosterama. 



Commefynece are distinguished from other Monocotyledonous families by their double perianth, 

 clearly separable, like that of Alismacca;, into calyx and corolla. Their habit and structure separate them 

 from Juncece, to which they were formerly united ; they approach Hesttaceee, and especially Xyridea, in 

 their antitropous embryo and sheathing leaves ; but these differ in several other characters, and notably 

 in the form and situation of their embryo, which is lenticular and pressed against the outside of the 

 albumen. Commclynece grow in the tropics of both worlds and especially the New ; a few are Australian, 

 where they extend to 35 south latitude. Some extend to 40 north latitude. 



Little is known of the properties of Commelynea, Many species possess an abundant mucilage, 

 which is alimentary after being cooked. The tuberous rhizomes of some contain, besides mucilage, 

 starch, which adds to their nutritive qualities ; such are Commelyna tuberosa, ccelestis, angustifolia, stricta, 

 &c. ; other Mexican species are administered in diseases of the liver. The rhizome of C. Rumphii'is praised 

 as an emmenagogue. The tubers of C. medico, are in use in China for coughs, asthma, pleurisy, and 

 strangury. The herbage of Tradescantia malabarica, cooked in oil, is employed in the treatment of 

 leprosy and ringworm. The Indians drink a decoction of Cyanotis axillaris for dropsy. Tradescantia 

 diuretica is prescribed in Brazil. 



