28 



CUSCUTACEAE. 



[Vol. III. 



2. Cuscuta Epithymum Murr. Thyme 



Dodder. Lesser or Clover Dodder. 



(Fig. 2957.) 



Cuscuta Epithymum Murr. in L. Syst. Ed. 13, 140. 1774. 

 Cuscuta Trifolii Bab. Phytol. I: 467. 1843. 



Stems filiform, red; flowers sessile in small 

 dense clusters, pinkish, about i // long. Calyx 

 variable, 4-5-lobed, more than one-half the length 

 of the cylindric corolla-tube, the lobes acute ; 

 corolla 4-5-lobed, the lobes erect, about one-half as 

 long as the tube, acute, its scales strongly incurved, 

 crenulate nearly or quite to the base; stigmas fili- 

 form; capsule circumscissile, capped by the wither- 

 ing corolla. 



On clover, Ontario (according to Fowler); Alder 

 Lake, N. Y., on Aster lateriflorus; Sellersville, and 

 Susquehanna Co., Pa. Introduced from Europe, where 

 it occurs on thyme, clover and other low plants. July- 

 Sept. 



3. Cuscuta arvensis Beyrich. Field 

 Dodder.. (Fig. 2958.) 



Cuscuta arve?isis Beyrich; Hook. Fl. Bor. Am. 

 2: 77. As synonym. 1834. 



Plant pale yellow; stems filiform, the 

 flowers nearly sessile in small clusters. 

 Calyx broad, 5-lobed, the lobes broad, obtuse; 

 corolla nearly campanulate, 5-lobed, the 

 lobes acute or acuminate, as long as the tube, 

 their tips reflexed, its scales large, ovate, as 

 long as or longer than the tube, densely 

 fringed all around with short irregular pro- 

 cesses; stamens not exserted; style shorter 

 than the ovary; stigmas capitate; capsule 

 depressed-globose, indehiscent, the wither- 

 ing corolla and usually the stamens per- 

 sistent at its base. 



On various herbs and low shrubs, New York 

 to Manitoba and the Northwest Territory, south 

 to Florida, Texas, Mexico and California. Also 

 in South America. July-Aug. 



4. Cuscuta Polygonorum Engelm. 

 Smart- weed Dodder. (Fig. 2959.) 



Cuscuta Polygonorum Engelm. Am. Journ. Sci. 



43: 342. pi. 6. f. 26-29. 1842. 

 C. chlorocarpa Engelm.; A. Gray, Man. 350. 1S48. 



Plant orange-yellow ; stems slender but 



rather coarse; flowers sessile or nearly so in 



dense clusters. Calyx short, 4-5 lobed, the 



lobes ovate-oblong, acute or acutish; lobes 



of the corolla 4 or 5, triangular-ovate, acute, 



mostly as long as the tube, the scales usually 



obsolete, wanting, or consisting of only 2 or 3 



slender processes on each side of the attached 



lower portion of the filament; filaments mostly 



slender; styles shorter than the ovary; stigmas 



capitate; capsule globose, the withering corolla 



persistent at its base. 



On Polygonums and other herbs, Minnesota to 

 Arkansas in the Mississippi Valley. Also in 

 Pennsylvania and Delaware. Range probably 

 more extensive. July-Sept. 



