184 CONVOLVULACEAE 



Main divisions of the leaf-blades linear, entire, the basal lobes usually deeply 

 cleft; sepals not auricled. 4. C. incanus. 



Calyx closely subtended and enclosed, by the large bracts. 

 Plants climbing or trailing: bracts cordate. 



Leaf-blades hastate; the basal lobes often sinuate-dentate, acute; stem and leaves 



glabrous or slightly hairy. 5. C. americanus. 



Leaf-blades more sagittate; basal lobes rounded, entire; stem and leaves densely 

 pubescent. 6. C. interior. 



Plants erect or decumbent; bracts oval or oblong. 7. C. Macounii. 



Family 108. CUSCUTACEAE. Dodder Family. 



1. CtJSCUTA (Tourn.) L. Dodder, Love-vine, Coral-vine. 



Stigmas elongate, linear; styles equal; capsule circumscissile. 



Corolla globose-urceolate; scales inside the corolla crenate. 1. C. gracilis. 



Corolla open-campanulate; scales inside the corolla deeply fringed. 



Calyx-lobes obtuse. 2. C. planiftora. 



Calyx-lobes acute. 3. C. Anthemi. 



Stigmas capitate; styles usually unequal. 



Capsule circumscissile; calyx and corolla-lobes acuminate; inflorescence urabel-Uke. 



4. C. umbellata. 

 Capsule indehiscent or bursting irregularly. 

 Calyx gamosepalous, usually not bracted. 

 Capsule depressed-globose. 



Lobes of the corolla triangular or lanceolate, acuminate or acute. 



Calyx-lobes acute or acuminate; corolla-lobes erect or somewhat spread- 

 ing, in fruit connivent; flowers pedicelled. 5. C. californica. 

 Calyx-lobes rounded; corolla-lobes strongly spreading with inflexed tips . 

 flowers subsessile. 6. C. arvensis. . 

 Lobes of the corolla oblong, very obtuse. 



Corolla deeply campanulate, 4-merous, about 2 mm. wide; tube longer 



than the calyx. 7. C cephalanthi. 



Corolla open-campanulate, about 4 mm. wide; tube shorter than the 

 calyx. 8. C plattensis. 



Capsule ovoid-globose, acute. 

 Corolla-lobes not incurved. 



Lobes of the corolla and the calyx obtuse. 



Flowers less than 2 mm. long ; calyx-lobes very short, rounded and 



denticulate. 9. C. denticulata. 



Flowers 2.S-3 mm. long; calyx-lobes ovate, not denticulate. 



Scales incurved over the ovary; styles about half as long as 



the ovary or longer. 10. C. Gronomi. 



Scales appressed to the corolla-tube; styles one-third to one- 

 fourth as long as the ovary. 11. C. curta. 

 Lobes of the corolla and calyx acute. 12. C. salina. 

 Corolla-lobes incurved at the apex. 



Capsule 4 mm. or less broad ; inflorescence rather open. 



13. C. indecora. 

 Capsule 5-6 nun. broad; inflorescence globular clusters. 



14. C. megalocarpa. 

 Calyx of 5 almost distinct and overlapping sepals, subtended by 2 or more similar 



bracts. 15. C. cuspidala. 



Family 109. POLEMONIACEAE. Phlox F.^mily. 



Calyx wholly herbaceous; leaves pinnately compound. 1. Polemonium. 



Calyx more or less scarious between the lobes, or the lobes spinulose-tipped and pungent; 

 leaves simple or pinnatifld, but not compound. 

 Calyx distinctly enlarging in fruit, not ruptm-ed by the capsule. 2. Collomia. 

 Calyx soon ruptured by the fruit, or if not ruptured, slightly if at all enlarged in 

 fruit and calyx-teeth spinescent. 

 Corolla strictly salver-shaped with a narrow throat. 



Perennials, with leaves opposite; seeds not mucilaginous when wetted. 



3. Phlox. 

 Annuals, with the floral leaves alternate; seeds mucilaginous when wetted. 



4. MlCROSTERIS. 

 Corolla campanulate, funuelform, trumpet-shaped, or if somewhat saiver-shaped. 



the throat open. 

 Anthers sagittate at the base; calyx-lobes and 3-5-cleft bracts densely woolly, 



pungent. 5. Welwitschia. 



Anthers not sagittate; calyx-teeth and bracts usually not woolly, but if some- 

 what so, not pungent. 

 Corolla elongate, with a narrow tube and funnelform or spreading throat. 

 Calyx-teeth either unequal in size or spinulose-laciniate, or both; pun- 

 gent-leaved annuals. 6. Navarrbti-i. 

 Calyx-teeth neither unequal nor spluulose-laclniate ; perennials or 

 non-pungent annuals. 

 Calyx not at all scarious in the sinuses; mostly undershrubs, with 

 pungent leaves. 7. Leptodactylon. 



