14(13). Calyx lobes triangular-ovate 11. C. indecora var. indecora. 



14. Calyx lobes lanceolate 11. C. indecora var. longisepala. 



15(11). Withered corolla about the top of the capsule (16) 



15. Withered corolla not at the top of the capsule (17) 



16(15). Calyx lobes denticulate, overlapping to enclose the corolla tube; scales 

 merely denticulate; corolla lobes erect 12. C. denticulata. 



16. Calyx lobes not enclosing the corolla tube; scales deeply fringed; corolla 



lobes widely spreading 13. C. Gronovii var. calyptrata. 



17(15). Calyx lobes mostly about half as long as the corolla tube 



13. C. Gronovii W'dv. Gronovii. 



17. Calyx lobes mostly about as long as the corolla tube 



13. C. Gronovii vaT. latifiora. 



18(2). Flowers pedicellate, loosely paniculate; sepals and bracts oval-orbiculate- 

 ovate 14. C. cuspidata. 



18. Flowers sessile, in dense compact clusters (19) 



19(18). Sepals and bracts acute 15. C. squamata. 



19. Sepals and bracts obtuse 16. C. compacta. 



1. Cuscuta umbellata H.B.K. Fig. 640. 



Flower stramineous, smooth or infrequently slightly papillate, commonly with 

 some pellucid glandlike cells, mostly 2-2.5 mm. long from base to corolla sinuses, 

 rarely much longer, with pedicels varying in length from shorter than to much 

 longer than the flowers, in dense or loose compound cymose clusters, the ultimate 

 umbellate divisions of 3 to 7 flowers; calyx lobes scarcely overlapping, triangular- 

 ovate to sublanceolate, acute to acuminate, smooth or slightly papillate, the 

 margins even or sometimes irregular; scales reaching the filaments, oblong- 

 subspatulate, fringed with medium-length processes; styles slender and longer than 

 the ovary; capsule depressed-globose, with a thickened collar about the inter- 

 stylar apertures, commonly easily circumscissile but some specimens tardily so, 

 surrounded by the withered corolla. Incl. var. reflexa (Coult.) Yunck. 



Mainly in the Tex. Trans-Pecos and Rio Grande Plains, Okla. (Cimarron Co.), 

 N.M. (Santa Fe, Sandoval, Union, Socorro, Sierra, Dona Ana, Valencia and Grant 

 cos.) and Ariz. (Pinal, Cochise, Pima and Yuma cos.); s. U. S., the W.I., Mex. and 

 n. S.A.; parasitic on a wide range of mostly low herbaceous hosts including 

 species of Polygonum, A triplex, Suaeda, Amaranthus, Alternanthera, Sesuvium, 

 Trianthema and Portulaca. 



2. Cuscuta Warneri Yunck. 



Stems filiform; flowers white, fleshy, 5-parted, about 2 mm. long when mature, 

 in few-flowered glomerules, on pedicels scarcely 1 mm. long; calyx strongly 

 papillate-hispidulous, reaching to above the middle of the corolla tube, divided 

 to about the middle into triangular-ovate lobes; calyx lobes thickened apically 

 to form a large prominent divergent acute cone-shaped or hornlike projection 

 0.5-0.75 mm. long, also with a small rounded corresponding projection at the 

 base; corolla papillate-hispidulous (especially downward); corolla lobes triangular- 

 ovate, acute, the margins slightly irregularly denticulate, suberect to strongly 

 inflexed-connivent, slightly projecting and angular at the base of the sinuses, 

 about half as long as the campanulate-suburceolate tube at maturity; stamens 

 shorter than the corolla lobes, incurved, the anthers ovoid and about as long as 

 the slightly subulate filaments; infrastamineal scales thin, oblong, sparingly toothed 

 at the truncate apex, bridged low, scarcely reaching the stamens; capsule globose, 

 indehiscent, rather thin and finely longitudinally striate when mature, with a 



1361 



