142 Convolvulus (Convolvulacece). [No. 18 



GUIDE TO THE SPECIES. 



(a) Stigmas, rounded or blunted. Seed-case, not splitting 



when ripe. 

 (b) Calyx with united sepals. Seed-case, flattened at the 



apex. 



(c) Flowers in dense rounded clusters. Corolla with 

 a short and wide tube, (i) C. chlorocarpa (Green- 

 Fruited Dodder). (2) C. arvensis (Field Dodder). 

 (c) Flowers in lengthened or angled clusters. Corolla 

 with a long slender tube. (3) C. tenuiflora (Nar- 

 row-Flowered Dodder). 

 (<) Calyx with united sepals. Seed-case pointed at the 



apex. 



(c) Corolla-lobes pointed and turned in. (4) C. de- 

 cora and var. (Comely Dodder). (5) C. inflexa 

 (Bending Dodder). 

 (c) Corolla-lobes blunt and spreading. (6) C. Gro- 



novii and var. (Gronovius' Dodder). 

 )<) Calyx with five distinct sepals. (7) C. compacta 

 (Compact Dodder). (8) C. glomerata (Coiled 

 Dodder). 



(a) Stigmas lengthened. Seed-case splitting when ripe. 

 (9) [C. epilinum] Flax Dodder. (TO) [C. epi- 

 thymum] Thyme Dodder. 



(i) Green-Fruited Dodder. C. chlorocarpa. Eng. 



Flowers, one twelfth inch, or a little more in length, in 

 dense, rounded clusters. Corolla, with a short and 

 wide tube. Corolla-lobes and calyx-lobes, usually four- 

 pointed, often longer than the tube. Scales, at the 

 base of the stamens, small and two-cleft, or oftener 

 reduced to minute teeth. 



Stem, coarse, orange color. 



Fruit, globular, with depressed apex ; pale, greenish- 

 yellow. 



Found, in damp ground from Wisconsin to Arkansas, also 



in Pennsylvania and Delaware. 

 A favorite support is the common Knotweed. 



