4 8 



CUSCUTACEAE. 



Vol. III. 



Family 21. CUSCUTACEAE Dumort, Anal. Fam. 20. 1829. 



I (odder Family. 

 White or yellow slender parasites, dextrorsely twining, the leaves reduced to 

 minute alternate scales, the small white, yellowish or pinkish flowers cymosely 

 clustered. Calyx inferior, 5-lobed or 5-parted (rarely 4-lobed or 4-parted), or 

 of 5 distinct sepals. Corolla campanulate, ovoid, urceolate or cylindric, 5-lobed 

 (rarely 4-lobed), the lobes imbricated in the bud, the tube bearing as many 

 fimbriate or crenulate scales as there are lobes and alternate with them, or these 

 sometimes obsolete. Stamens as many as the corolla-lobes and alternate with 

 them, inserted in the throat or sinuses above the scales, short-exserted or included; 

 filaments short or slender; anthers short, ovate or oval, obtuse, 2-celled, the sacs 

 longitudinally dehiscent. Ovary globose to oblong. 2-celled; ovules 2 in each 

 cavity ; styles 2, terminal, separate, or rarely united below ; stigmas linear or capi- 

 tate. ' Capsule globose or ovoid, circumscissile, irregularly bursting or indehiscent. 

 1-4-seeded. Seeds glabrous, globose or angular; embryo linear, terete, curved 

 or spiral, its apex bearing 1-4 minute scales, endosperm fleshy ; cotyledons none. 



1. CUSCUTA [Tourn.] L. Sp. PL 124. 1753. 

 Characters of the family. The filiform twining stems are parasitic on herbs and shrubs 

 by numerous minute suckers. The seeds germinate in the soil and the plantlet attaches itself 

 to its host, its root and lower portion soon perishing. The subsequent nutrition of the 

 parasite is apparently wholly through its suckers. [Name from the Arabic] 



About 100 species, of wide geographic distribution. Besides the following, some 15 others 

 occur in the southern and western parts of North America. Known as Dodder, or Strangle-weed. 

 Type species: Cuscuta europaca L. 



* Corolla-scales crenulate; stigmas slender; capsule circumscissile; introduced species. 

 Scales crenulate above, not incurved. 1. C. Epilinum. 



Scales crenulate all around, strongly incurved. 2. C.Epithymum. 



** Corolla-scales fringed; stigmas capitate; capsule indehiscent; native species. 

 Sepals united below into a gamosepalous calyx. 



Flowers very nearly sessile ; corolla persistent at the base of the capsule. 



Corolla-scales ovate, fringed all around ; calyx-lobes obtuse. 3. C. arvensis. 



Corolla-scales abortive, or of a few processes; calyx-lobes acutish. 4. C.Polygonorum. 



Flowers distinctly pedicelled ; corolla enclosing or capping the capsule, or at length deciduous. 

 Tips of the corolla-lobes incurved or reflexed. 



Scales ovate, fringed all around ; capsule enclosed by the corolla. 5. C. indecora. 



Scales abortive, or of a few slender processes ; corolla capping the capsule. 6. C. Coryli. 

 Corolla-lobes spreading or recurved. 



Scales small, irregularly fringed ; capsule depressed-globose. 

 Scales long, fringed mainly above; capsule pointed.' 



Corolla iVi" long; capsule globose, short-pointed. 8. 



Flowers a" 3" long : capsule oval, long-pointed. 9- 



Sepals separate, subtended by similar bracts. 



Flowers cymose, pedicelled ; scales short ; bracts entire. 

 Flowers closely sessile in dense clusters ; bracts serrulate. 

 Bracts few, broad, appressed ; styles as long as the ovary. 



C. Cephalanlhi. 



C. Gronovii. 

 C. ro strata. 



10. C. atspidata. 



11. C. compacta. 

 Bracts numerous"'narrow, their tips recurved; styles longer than the ovary. 12. C.parado.xa. 



i. Cuscuta Epilinum Weihe. Flax Dodder. 

 Fig. 344-2. 



Cuscuta Epilinum Weihe, Archiv. Apoth. 8: 54. 1824. 

 Cuscuta densiflora Soyer-Willem. Act. Soc. Linn. Pans 

 4: 281. 1826. 



Stems very slender, yellow or red; flowers^sessile 

 in dense clusters, yellowish white, about ii" long. 

 Calyx hemispheric, 5-lobed, the lobes acute, nearly 

 as long as the corolla-tube; corolla yellowish-white, 

 short, cylindric, becoming urceolate, 5-lobed, the 

 lobes ovate, acutish, spreading, its scales short, erect, 

 less than one-half the length of the tube, 2-cleft or 

 emarginate, crenulate above, the crenulations not ex- 

 tending to the base; stigmas linear-filiform; capsule 

 circumscissile. the withering-persistent corolla borne 

 on its summit. 



On flax, Nova Scotia to New Jersey and Pennsylvania. 

 Introduced from Europe. Native also of Asia. July- 

 Aug. 



