prominent thickened shallowly 4-lobed cuplike or collarlike apex, enveloped by 

 the corolla when mature; styles slender, scarcely exceeding the corolla, the 

 stigma globose. 



Growing on Phyla cuneifolia about wet bank of shallow pond in Ariz. (Coconino 

 Co.), June-Aug.; also Ut. 



3. Cuscuta obtusiflora H.B.K. var. glandulosa Engelm. Fig. 640. 



Flowers 1.5-2 mm. long from base to corolla sinuses, 5-merous, commonly 

 with numerous enlarged pellucid glandlike cells, subsessile in scattered moderately 

 open glomerate-cymose clusters; calyx lobes nearly enclosing the corolla tube, 

 commonly unequal (one smaller than the others), ovate, obtuse, scarcely over- 

 lapping at base; corolla lobes somewhat shorter than the tube, ovate to ovate- 

 oblong, obtuse to acutish, upright to spreading; scales about reaching the filaments, 

 oblong, fringed about the top, sometimes bifid or truncated; styles stoutish and 

 subulate, shorter than or about equaling the ovary; capsule depressed-globose, 

 interstylar aperture large, the withered corolla remaining at the base. C. glandulosa 

 (Engelm.) Small. 



Occasional throughout Tex. but most frequent in the s.e. section, and Okla. 

 (Haskell and Muskogee cos.); also the Gulf States, W.I., Mex. and S.A.; most 

 frequently on species of Polygonum but also on other plants as Justicia americana. 



4. Cuscuta Polygonorum Engelm. Smartweed dodder. Fig. 640. 



Flowers 1-1.5 mm. long from base to corolla sinuses, mostly 3- or 4-merous, 

 subsessile in compact glomerulate clusters; calyx lobes triangular-ovate, often 

 unequal, not overlapping at base, as long as or longer than the corolla tube; 

 corolla lobes triangular, acute, upright, as long as or longer than the tube; scales 

 oblong, about reaching the filaments or commonly shorter, mostly bifid, the 

 processes mostly few and near the top; styles shorter than the ovary, becoming 

 subulate and divergent; capsule globose or obpyriform, commonly depressed, 

 appearing cubical about the maturing seeds, interstylar aperture large and rhombic. 



From N.E. and Ont., w. and s.w. to Neb., Okla. ( Waterfall) and Tex. {fide 

 Small); mostly on species of Polygonum but also on species of Penthorum, 

 Impatiens, Lycopus and others. 



5. Cuscuta Cephalanthi Engelm. Button-bush dodder. Fig. 640. 



Flowers about 2 mm. long from base to corolla sinuses, 3- or 4-merous, rarely 

 5-merous, with numerous pellucid glandlike cells, sessile or subsessile in spicate 

 or paniculately cymose clusters, frequently originating endogenously in the 

 regions of the haustoria. the clusters at first open but soon becoming compact as 

 the capsules mature; calyx shorter than the corolla tube, deeply divided, the 

 ovate-oblong lobes obtuse and slightly overlapping at the base, the margins often 

 minutely irregular; corolla lobes much shorter than the tube, ovate, obtuse, erect 

 to spreading; scales narrowly oblong, about reaching the filaments, fringed with 

 scattered processes; styles slender, about equal to or slightly longer than the 

 ovary; capsule depressed-globose or globose, commonly only 1 or 2 seeds matur- 

 ing, more or less lopsided when but one seed matures, the walls thin, capped by 

 the withered corolla that is easily removed. 



Rare in n.-cen. Tex., (?) Okla. and Ariz. (? Cochise Co.); from Me. and Va., 

 w. to Wash., and Calif., less frequently s. to Mex.; parasitic on a wide variety 

 of woody and herbaceous hosts including species of Salix, Boehmeria, Justicia, 

 Teucrium, Physostegia, Cephalanthus, Vernonia, Solidago and Aster. 



6. Cuscuta pentagona Engelm. Fig. 640. 



Flowers 1-1.5 mm. long from base to corolla sinuses, the protruding capsules 

 soon causing the flowers to appear larger, commonly with pellucid glandlike cells, 



1362 



