CONVALLABIA 



days ; after that admit the light gradually, and when 

 in full flower give them the full light, but never much 

 sunlight, and avoid draughts. A dozen or 20 pips can 

 be forced the same way in a 5- or 6-inch pot. The 

 flowers should be cut about 24 hours before using, and 

 placed in jars of cold water. This prevents wilting 

 ^^^"^ "^^-J' William Soott. 



C0NV6LVTTHJS (Latin, convolve, to entwine ) . Convol- 

 vul&.eei^. Includes Calystegia. Bindweed. A genus 

 of about 175 species, widely distributed 

 intemperate and tropical regions. Annual 

 or perennial herbs, sometimes suffrutes- 

 oent, twining, trailing, erect or ascend- 

 ing, with filiform, creeping rootstocks : 

 Ivs. petiolate, entire, toothed or lobed, 

 generally cordate or sagittate : fls. axil- 

 lary, solitary or loosely oymose, mostly 

 opening only in early morning ; corolla 

 <;ampanulate or funnel-form, the limb 

 plaited, 5-angled, 5-lobed or entire. The 

 botaniciil distinction between Convolvulus 

 and Calystegia is not suificiently well 

 marked to warrant retaining the latter as 

 a separate genus. When the fls. of C. oc- 

 ^identalis are borne singly, the calyx 

 bracts are broad and Calystegia- like ; 

 -when borne in clusters the bracts are 

 greatly reduced. g. -^^ Fletcher. 



The species thrive in a variety of soils 

 without especial care. The greenhouse 

 species do best in a soil with considerable 

 fiber. The hardy perennials are usually 

 prop, by dividing the roots, otherwise by 

 cuttings or seeds, the tender species pre- 

 ferably by cuttings. O. tricolor is the most 

 important of the hardy annuals. It may also be started 

 in the greenhouse, and makes an excellent plant for 

 the hanging basket. All are vigorous growers, and 

 may become troublesome weeds in some places if not 

 kept within bounds. C. Japonicus and C. Septum 

 should be used with caution. This is the chief reason 

 why the hardy perennials are not often found in well- 

 kept gardens, except along wire fences or lattice 

 screens, where the turf is laid up close so as to allow 

 only a narrow border for the roots. The double-flowered 

 form of C. Japonicus is seen to best advantage in half- 

 wild places, or on rocky banks, where shrubs make but 

 a stunted growth. Here it will grow luxuriantly, form- 

 ing graceful festoons from branch to branch, and cover- 

 ing the ground with a pretty mantle of green. 



Cult, by J. B. Keller. 



A. Calyx with 2 membranaceous tracts at the base; 



peduncles usually 1-fld, {Calystegia.) 



B. Stem prostrate, 8 in, to 2 ft. high : peduncle usually 



shorter than the Ivs. 



villdsus, Gray {Calystegia villbsa, Kellogg). Plant 

 densely white-villose throughout : stem prostrate, 

 scarcely twining : Ivs. slender-petioled, reniform-has- 

 tate to sagittate, the upper acuminate, 1 in. or less 

 long, the basal lobes often coarsely toothed: bracts oval 

 or ovate, completely enclosing the calyx: fls. cream-yel- 

 low, 1 in. long. Calif. Perennial. 



BE. Stem twining or trailing, S-10 ft. high: peduncle 



exceeding the Ivs. 

 Japfinicus, Thunb. (Calystegia puMscens, Lindl.). 

 California Rose. Fig. 542. Hardy perennial, herba- 

 ceous twiner: growth very vigorous, often 20 ft. : whole 

 plant more or less densely and minutely pubescent: 

 Ivs. hastate, lanceolate, obtuse or broadly acute, with 

 angular or rounded lobes at the base : variable, oc- 

 casionally without lobes, rarely sharp lanceolate : fls. 

 bright pink, 1-2 in. broad, produced freely during the 

 summer months and remaining expanded for several 

 days. Japan and B. Asia. The double form is now 

 naturalized from southeastern N. Y. to D. C. and 

 Mo. P. M. 13 : 243. F. S. 2 : 172. B. R. 32 : 42.- 

 The double form is completely sterile, with narrow, 

 wavy petals, irregularly arranged, the outer somewhat 

 lacerate. A valuable decorative plant for covering 



CONVOLVULUS 



367 



stumps and walls. In rich soil the roots spread rapidly, 

 and will smother out all other plants unless confined in 

 tubs. The Calystegia pubescens of Lindley has been 

 wrongly referred to Ipomcea hederacea, but the two 

 plants are very different, the former being perennial 

 and the latter annual. See .Journ. Hort. Soc. 1:70 (1846). 

 The plant is commonly confounded with C. Senium. 



occidentilis, Gray. Hardy perennial, herbaceous or 

 with suffruteseent base: stem twining, several ft. high, 

 glabrous or minutely pubescent : Ivs. from angulate- 



542. Convolvulus Japonicus. 



(XH.) 



cordate, with a deep and narrow sinus, 

 to lanceolate - hastate, the posterior 

 lobes often 1-2-toothed : peduncle 1-fld. 

 or proliferously 2-3-fld. : bracts ovate 

 or lanceolate, usually completely enclosing the calyx, 

 variable : corolla white or pinkish, 1-2 in. long ; stig- 

 mas linear. Dry hills, Calif. -Int. 1881, by Gillett. An 

 admirable plant for rockeries. 



S^pium, Linn. (Calystegia S^piMJK,R. Br. ). Rutland 

 Beauty. Fig. 543. Perennial trailer, 3-10 ft. long, gla- 

 brous or minutely pubescent: Ivs. round-cordate to del- 

 toid-hastate, the basal lobes divaricate, entire or angu- 

 late: fls. white, rose or pink, with white stripes. F.S. 

 8:826. B.M.732. A.G.12:638. Gn. 50: 1098. -A very 

 variable species. Cosmopolitan in temperate regions. 

 An insidious weed in moist soil. 



AA. Calyx without bracts : peduncle 1-G-fld. (Eiicon- 

 volvulus .) 

 B. Stem prostrate, trailing, glabrous or minutely 

 pubescent. 

 Maurit&nicus, Boiss. Strong perennial roots : stem her- 

 baceous, slender, prostrate, rarely branched, minutely 

 villose: Ivs. alternate, round-ovate, obtuse, short-peti- 

 oled: fls. blue to violet-purple, with a lighter throat, 

 1-2 in. across, very handsome. Africa. B.M. 5243. F.S. 

 21: 2183. Gn. 39: 788. -A free bloomer through the sum- 

 mer. On dry banks each plant forms a dense tuft which 

 throws up many graceful shoots. Not hardy north of 

 Phila. 



