130 SAXIFRAGACEiE. 



Sub-order III. HYDEANGE^E. 



fihvubs; leaves opposite; petals valvate in the bud; calyx-tube coherent toitft the ovary. 



7. HYDRANGEA. Gronov. 



Gr. hudor, water, aggion, a rase; in allusion to the form of the capsule. 



Calyx-tube hemispherical, 8 to 10-ribbed, adherent to 

 the ovary; limb 4 to 5-toothed, persistent. Petals ovate, 

 sessile. Stamens 8 to 10, slender. Styles 2. Capsule 

 2-celled, many-seeded, crowned with the 2 diverging styles, 

 opening by a hole between the styles. — Shrubs with opposite 

 petioled lea ves and n umcrous flowers in compound cynics. The 

 margined flowers are often sterile and radient. 



1. H. ARBORESCENS, L. Wild Hydrangea. 



Leaves ovate, obtuse, or cordate at base, pointed, serrate, nearly smooth ; flowers 

 in fastigiate cymes. 



A handsome shrub, native along the banks of the Susquehanna, flowering in 

 June. Stem 5 to 6 feet high. Fertile flowers small, -white, yellowish or roseate, 

 very numerous. In cultivation, the marginal flowers become radiate. 



2. H. QUERCIFOLIO, Bartram. Oah-Uaved Hydrangea. 



Leaves deeply sinuate-lobed, dentate, tomentose beneath. Cymes paniculate, 

 radiant; the sterile flowers very large and numerous. Native of Florida. A 

 handsome shrub from 3 to 5 feet high^ with very large leaves, and showy flowers 

 at first a dull white becoming reddish. 



3. H. hortensis, L. Changeable Hydrangea. 



Leaves elliptical, crowned at each end, dentate-serrate, strongly veined, smooth. 

 Cymes radiant. Flowers mostly radiant. Native of China. This beautiful species 

 has long been cultivated for its showy flowers which are at first green but pass 

 successively through straw-color, white, purple and pink. The var. H. Japonica 

 has the central flowers all fertile, bluish-purple, hardy about Philadelphia. 



Sub-order IY. PHILADELPHEA 



Shrubs: leave* opposite; petals convolute in oestivation ; capsule 3 to ArCeUed, loculiddal 



8. PHILADELPHUS. Linn. 



Name from Fhiladelphus, King of Egypt. 



Calyx 4 to 5-parted, half-superior, persistent. Corolla 

 4 to 5-petalled. Style 4-cleft. Stamens 20 to 40, shorter 

 than the petals. Capsule 4-celled, 4-valved, with loculici- 

 dal dehiscence. Seeds many, ariled. — Shrubs, with op>posiie 

 exstipulate leaves and showy ichite floivcrs. 



1. P. GRANDIFLORUS, Willd. Large-flowered Syringa. 



Leaves ovate, acuminate, denticulate, 3-veined, axils of the veins hairy. Stigmat 

 4, linear. Style undivided. A handsome shrub 4 to 8 feet high, with long slender 

 branches. Native at the South, cultivated for its large showy white flowers, which 

 are home in a terminal umbel of 2 or 3 together. 



