343 Monography of the North American Cuscutinece. 



This Texian species is nearly related to C, pentagona : the size 

 of the flowers, shape of corolla and the scales, are the same ; but 

 it is easily distinguished by the loose and few-flowered cyme, 

 and by the tuberculate or hispid-campanulate (not pentagonous, 

 smooth, and membranaceous) calyx. 



7. OUSCUTA POLYGONORUM, n. Sp. 



Stem low, branching ; flowers subsessile, glomerate, mostly 

 4-parted ; tube of the corolla campanulate, nearly equal to the 

 acute campanulate or spreading lobes, and the acute segments of 

 the calyx ; stamens as long as the limb ; the scales mostly bifid, la- 

 ciniate, appressed ; styles as long as the depressed ovary ; remains 

 of the corolla persistent at the base of the depressed capsule. 



On different species of Polygonum, also on Lycopus, Pentho- 

 rum, and other plants in the neighborhood. August and Sep- 

 tember. 



This is a much lower plant than C. Saururi, etc., with orange- 

 colored stems, twining round the Polygona in overflowed places, 

 the bottoms of sink-holes, or margins of ponds, west of St. Louis, 

 where in the year 1839 my friend F. Lindheimer, now in Texas, 

 to whose zeal and kindness I owe many specimens from that 

 interesting country, first discovered it. In the following year, I 

 found it on the banks of Illinois river, near Peru, in thickets 

 formed by immense Ambrosice, with Bidens, Spartina, etc. 

 Whether any Polygonum was there I cannot recollect, having 

 at the time paid no particular attention to this point. The flowers 

 of the specimens from Peru are a little more peduncled, and the 

 very acute segments of the calyx rather longer than the tube of 

 the corolla ; but I observe no other difference. 



This and C. Saururi, are easily distinguished from the others 

 by their orange-colored stems, their larger open campanulate flow- 

 ers, with the remains of the corolla always at the base of the 

 capsule. The scales of the filaments in C Polygonorum are 

 intermediate between C. Coryli and C. Cephalanthi in shape ; 

 but are more laciniate than in the former. They are appressed 

 to the corolla ; so that the large depressed ovary appears naked 

 in the open tube ; while in C. Saururi it is covered by the con- 

 vergent or inflexed multifid scales. 



Note. — Since the manuscript of this article has been communicated to the 

 American Journal, my attention has been directed to one or two species of Cus- 



