Var. cynanchoides [Funastrwn cynanchoides (Dene.) Schltr., Philibertella 

 cynanchoides (Dene.) Vail] is widespread in the western half of Texas and it 

 typically has broadly triangular-lanceolate leaves, whereas var. Hartwegii (Vail) 

 Shinner {S. heterophyllum of auth.), with linear to linear-lanceolate leaves, occurs 

 only in the Trans-Pecos. Few specimens have been seen that are intermediate 

 between these two varieties. The flowers of var. cynanchoides are also usually 

 greenish-white while those of var. Hartwegii are usually purplish or pinkish, 



Fam. 111. Convolvulaceae Juss. Morning Glory Family 



Annual or perennial herbs, vines or shrubs (trees south of our area); leaves 

 alternate, simple or compound, entire, toothed or lobed (wanting in Cuscuta), with- 

 out stipules; flowers axillary or terminal, solitary or cymose, perfect, 5-merous; 

 sepals 5, equal or unequal (often overlapping laterally), separate or united in 

 basal portion; corolla gamopetalous, regular (rarely with curved tube or slightly 

 irregular limb), 5-angled to deeply 5-lobed; stamens epipetalous; ovary 2- (occa- 

 sionally 1- or 3- to 5-) celled, free from the calyx; fruit a 1- to several-seeded 

 capsule (indehiscent in some species). 



About 1,600 species in about 30 to 50 genera, in tropical (chiefly) and temper- 

 ate regions of both hemispheres. 



1. Leafless parasitic annual twiners, not ground-rooting by flowering time 



6. Cuscuta 



1. Leafy or leafy-bracted ground-rooting annual or perennial twiners, trailers, 



erect herbs or shrubs (2) 



2(1). Stigmas linear or oblong, more than twice as long as broad 4. Calystegia 



2. Stigmas globose to reniform or flat-topped, as broad as long or broader 



(minute and scarcely larger than style in some species) (3) 



3(2). CoroHa shorter than or up to twice as long as calyx, with prominent lobes 

 one third to three fourths its total length, the lobes as long as wide 

 or longer (4) 



3. Corolla more than twice as long as the calyx, shallowly lobed (lobes broader 



than long) or merely angled (5) 



4(3). Leaf blades orbicular-ovate to orbicular-reniform, cordate, becoming long- 

 petioled 1. Dichondra 



4. Leaf blades elliptic to oblong-lanceolate or reduced to small bracts, very short- 



petioled or sessile 2. Cressa 



5(3). Style usually 2-branched (rarely with 1 branch suppressed); stigmas 

 minute, little larger than diameter of style 3. Stylisma 



5. Style unbranched; stigma globose and undivided or with 2 or 3 subglobose 



lobes 5. Ipomoea 



1. Dichondra Forst. & Forst. Pony-foot 



Creeping or trailing perennials; leaves long-petioled; blades orbicular-ovate to 

 orbicular-reniform, entire; flowers very small, axillary, solitary or paired, long- 

 pedicelled; sepals 5, united at base; corolla shallowly funnelform, deeply 5-lobed, 

 light-green or white; fruit indehiscent or dehiscent, 2- or 4-seeded. 



About 15 species, in tropical and warm-temperate regions of both hemispheres. 



1. Pedicel straight; calyx lobes 2 or 3 times as long as wide 1. D. carolinensis. 



1. Pedicel abruptly recurved near summit; calyx lobes 1.5 to 2 times as long as 

 wide (2) 



1350 



