430 NATURAL HISTORY OF PLANTS. 



me n.— A. perennial subacaulescent glandular-pilose herb; rhizome 

 thin ; leaves radical petiolate rotundate-cordate, sinuate-dentate, 

 palmiveined, ribbed ; petiole sheathing ; flowers in loose elongated 

 simple racemes, bare at base ; pedicels thin bracteate at base {Chili). 

 See p. 340. 



VI. HYDRANGEA. 



23. Hydrangea L. — Flowers usually 2-morphous ; exterior of 

 inflorescence often sterile subapetalous, with much enlarged calyx. 

 Receptacle concave in fertile flowers, usually sacciform ; perianth 

 and androceum inserted on margin. Sepals 4, 5, in fertile flowers 

 equal, small, sometimes dentiform ; in sterile broadly petaloid veined 

 unequal (exterior usually larger). Petals 4, 5, valvate. Stamens 

 8-10, 2-seriate; filaments slender, inserted outside base of epigynous 

 disk ; anthers short 2-celled, subintrorsely or marginally rimose. 

 Germen inferior included in concavity of receptacle ; cells 2-4, 

 complete or incomplete ; placentas as many, more or less introflexed, 

 co -ovulate ; style 2-4-branched nearly from base or to a variable, 

 depth ; branches stigmatose at apex or within. Capsule mem- 

 branous, topped by calyx and styles ; cells 2, 4, dehiscent from 

 vertex between styles. Seeds co , minute, ascending or transverse ; 

 testa membranous, sometimes produced beyond nucleus ; albumen 

 thin fleshy ; embryo axile cylindrical ; cotyledons short. — Trees, or 

 more often shrubs, sometimes climbing ; leaves opposite petiolate, 

 often persistent, entire, serrate or lobate, exstipulate ; flowers in 

 cymes, often 1 -parous, subcorymbose ; bracts of inflorescence basilar 

 deciduous {Eastern and Central or Southern mountainous Asia, Java, 

 North East and South- West America). See p. 340. 



24. Platycrater Sieb & Zucc.— Flowers of Hydrangea, 4, 5-me- 

 rous, or more rarely 2, 3-merous. Stamens co , epigynous, co -seriate, 

 anthers varying in form, sometimes subcordate-truncate {Cardiandra), 

 at apex stigmatose, more or less capitate. Capsule dehiscent between 

 styles. Seeds co , ascending oblong • testa thin reticulate produced 

 into a wing on both sides; embryo albuminous. — Shrubs; leaves 

 opposite or alternate {Cardiandra) exstipulate, serrate or dentate, de- 



