338 X.ITURAL mSTORY OF PLANTS'. 



GENERA. 



1. Cistus T. — Flowers regular, generally hermaphrodite; recep- 

 tacle rather convex. Sepals 5, more rarely 3, unequal ; 2 exterior 

 often much smaller ; 3 interior usually convolute ; prsefloration 

 usually imbricated. Petals 5, more or less opposite sepals, some- 

 times alternate, very shortly unguiculate, imbricate or usually con- 

 torted, very fugacious. Stamens co, hypogynous ; filaments free, ex- 

 terior sometimes antherless ; anthers 2-locular ; cells longitudinally 

 introrsely or laterally dehiscing. Germen free sessile, 1-locular; 

 septa parietal 3 or 5, alternipetalous, more rarely 6-12, more or less 

 prominent, sometimes inwardly contiguous ; style simple, very short 

 or almost wanting, sometimes cylindrical elongated, apex dilated 

 and divided into short lobes (apices of septa) more or less con- 

 spicuous stigmatiferous ; ovules on each placenta 2, or oftener co, 

 funicle often long extended ; orthotropous or very rarely more or 

 less adnate to funicle subanatropous. Capsule dehiscent from apex 

 to a greater or less distance into valves equal in number to and 

 bearing placentas at middle within. Seeds co ; testa crustaceous 

 (oftener damp exterior mucilaginous) ; albumen farinaceous or sub- 

 cartilaginous ; embryo subcentral or oftener excentric, curved con- 

 volute, 2-plicate or conduplicate, more rarely suberect ; cotyledons 

 flat or semiterete ; radicle remote from hilum or more or less near 

 (adnate to funicle).: — Herbs, undershrubs, or shrubs ; leaves opposite 

 or sometimes alternate, simple, subentire ; stipules 0, or small, 

 sometimes foliaceous ; flowers solitary terminal or falsely racemose 

 (cymose) secund (Southern and Mediterranean Europe, Mediterranean 

 Africa, South Western Asia). See p. 330. 



2. Heliantliemum T. — Flowers nearly of Cistus, some 2-morphous; 

 sepals 3-5. Petals 5, or more rarely 3, sometimes 0. Stamens cc, 

 exterior sometimes sterile (Fumana). Germen 3-merous ; placentas 

 or semisepta 3 ; style often articulate, form longitudinal and 

 varied, apex stigmatiferous capitate or cristate-3-lobed. Capsule 

 3-valved. Seeds co ; embryo uncinate, 2-plicate or circumflexed. — 



