774 



CONVOLVULACEAE 



Convolvulus 



Jan. 



Feb 



Mar. 



Apr. 



May 



June 



July 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



Miles 



50 



Map 1669 



Convolvulus spithamaeus L. 



50 



Map 1670 



Convolvulus japonicus Thunb. 



7. Cuscuta Cephalanthi Engelm. Buttonbush Dodder. Map 1666. 

 This species, also, prefers plants of low ground for hosts. The host plants 

 of my specimens are as follows: 7 on Aster, 1 on Cephalanthus, 1 on 

 Dianthera, 1 on Physostegia, 1 on Rhus, 3 on Salix, and 1 on Teucriiim. 



Maine to Wash, and Oreg., southw. to Va., Tenn., and Tex. 



8. Cuscuta Coryli Engelm. Hazel Dodder. Map 1667. On plants about 

 lakes and in low woods. The hosts of my specimens are as follows : 1 on 

 Aster, 1 on Campsis, 1 on Corylus, 1 on Prunella, 1 on Sanicula, 2 on 

 Solidago, and 2 on Stachys hyssopifolia. 



R. I. to Man., southw. to Va., Tex., and Ariz. 



9. Cuscuta Polygonorum Engelm. (Cuscuta obtusiflora of Gray, Man., 

 ed. 7.) Smartweed Dodder. Map 1668. On plants of low ground about 

 ponds and lakes and in low woods. The hosts of my specimens are as 

 follows: 1 on Aster, 4 on Bidens, 1 on Polygonum, and 1 on Xanthium. 



Md. to Minn, and Nebr., southw. to Tenn., and possibly Tex. 



6993. CONVOLVULUS [Tourn.] L. Bindweed 



Bracts large, surrounding and inclosing the calyx; stigmas oval or oblong. 



Plants short, erect or ascending; petioles mostly less than a fourth as long as the 



blade 1. C. spithamaeus. 



Plants long, trailing or twining; petioles mostly more than a fourth as long as the 

 blade. 



Flowers double; plants escaped from cultivation 2. C. japonicus. 



Flowers single; plants native. 



Peduncles mostly much longer than the petioles; flowers commonly only 1 in an 

 axil. 

 Leaves glabrous, sometimes somewhat pubescent, rarely densely pubescent; 

 basal lobes mostly hastate (turned outward) ; peduncles not wing-angled. 



3. C. sepium. 



Leaves densely pubescent; basal lobes rounded or sagittate (lobes not turned 



outward) 4. C. repvns. 



Peduncles mostly shorter than the petioles; flowers commonly 2 in each axil. 



3a. C. sepium var. fraterniflorus. 



Bracts small, much smaller than the calyx and at some distance below the flower; 

 stigmas filiform 5. C. arvensis. 



