INCAEVILLEA 



THE BULB BOOK 



IPOMjEA 



to a tree called Icaco). Nat. Ord. 

 Oleacese. — The only species that has 

 been introduced, and is still practi- 

 cally unknown, is 1. Mannl, a native 

 of the Gulf of Guinea. It is a hot- 

 house perennial with a large smooth, 

 roundish, tuberous root-stock 6 to 12 

 ins. in diameter, from which arise 

 slender climbing stems, bearing 

 opposite, elliptic, truncated leaves of 

 membranous texture. The small 

 silky yellow blossoms with protrud- 

 ing stamens appear about October, in 

 short cymes from the axils of the 

 leaves. {Bot. Mag. t. 6260.) 



This species will grow in sandy 

 loam and leaf-mould, and requires 

 plenty of heat and moisture. In- 

 creased by cuttings of the young 

 shoots in spring, inserted in bottom 

 heat under a bell-glass or frame. 



INCARVILLBA (in honour of Pere 

 dllncarville, a Chinese Jesuit mission- 

 ary, and correspondent of Bernard de 

 Jussieu). Nat. Ord. Bignoniaceae. — 

 There are several species of Incar- 

 villea, some annuals and biennials, 

 but the only perennials of a tuberous 

 character are those here mentioned. 



I. Delavayl. — A charming hardy 

 herbaceous perennial, n-ative of China, 

 with large fleshy, spindle-shaped 

 roots, and large leaves pinnately cut 

 into numerous elliptic, crenulate 

 segments. The large rosy-carmine 

 tubular flowers, spotted with yellow 

 and brown at the base, are borne in 

 loose trusses during the summer 

 months, on stems l^ to 2 ft. high. 

 {Rev. Hort. 1893, t. 544.) 



This species flourishes in ordinary 

 good garden soil of a gritty character, 

 and should be grown in sunny situa- 

 tions to secure the depth of colour in 

 the flowers. It may be easily raised 

 from seeds sown in spring in gentle 

 heat, or by means of cuttings detached 

 from the tubers in spring, and inserted 



in sandy soil under a bell-glass or 

 light. 



I. grandlflora, also from China, is 

 like /. Delavayi, but has shorter 

 leaves and leaflets, also a shorter 

 flower-stem bearing a few rosy-red 

 flowers {Oard. Chron. 1898, xxiv. 8). 

 It is somewhat more tender than /. 

 Ddayayi, but is on the whole a finer 

 flowering plant. 



I. variabilis. — A native of W. China, 

 1 to 1| ft. high, with pinnate leaves, 

 and loose erect racemes of small rose- 

 purple tubular flowers {Bot. Mag. 

 t. 7651). 



lFOM.^A {ips, Bindweed ; omoios, 

 similar). Nat. Ord. Convolvulacese.— 

 This genus contains some 300 to 400 

 species according to various authori- 

 ties. They are divided into annuals 

 and perennials, some being hardy, 

 others requiring the protection of a 

 greenhouse or hothouse, but all alike 

 in having climbing and twining stems 

 like our Common Bearbind (Convol- 

 vulus), and beautiful funnel-shaped 

 flowers. Representatives of the genus 

 are found in almost every part of the 

 subtropical and tropical world, conse- 

 quently cultural conditions vary. 

 There are comparatively few species 

 having tuberous root-stocks, those 

 mentioned here being amongst the 

 best known. They nearly all lose 

 their leaves and stems in winter, so 

 that they enjoy a period of repose 

 during that season. Very little or no 

 water is then required. In spring, 

 however, when growth recommences 

 plenty of moisture is necessary. A 

 compost of fibrous loam with a little 

 leaf -mould and sand suits most of them 

 perfectly. Propagation of the tuber- 

 ous species is effected by division of 

 the roots, or by cuttings from them in 

 spring, inserted'in sandy soil under a 

 light. 



I. Batatas. — The "Sweet Potato" 



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