68 ILLINOIS BIOLOGICAL MONOGRAPHS [158 



mostly about the upper part but sometimes at the base; intrastylar 

 aperture rather large; styles usually convergent; seeds about 2-2.8 mm. 

 long, slightly rostrate; hilum transverse or oblique. 



This species is closely allied to C. gronovii. It differs from it, however, 

 in the possession of a much larger capsule, shorter styles, and usually bifid 

 and truncated scales. 



Type locality: "Northwestern America." Range: Minnesota to 



Wyoming and south to Colorado and New Mexico. 



Specimens examined: United States: Southwest Kansas to New Mexico (Bell in 1867), 

 Northwest America (Fremont's 3rd Exped. 79, the type, in the Engelmann Herb.). Min- 

 nesota; Chatfield (Hall 3), Preston (Hill 66-1876, Leach in 1861). N. Dakota; Benson 

 (Lunell in 1909, 1912), Leeds (Lunell in 1907), Walhalla (Waldron 1697), Valley City (Perrine 

 in 1896), Ward Co. (Lunell in 1908), Dunseith (Lunell in 1907). S. Dakota; Black HiUs 

 (Petersen in 1909). Nebraska; Ashland (Williams 355). Colorado; Huerfano Co. (Greene 

 in 1913), Canyon City (Brandegee 704), Platte Canyon, Dome Rock (Jones 571), La Veta 

 (Vreeland 670, the type of C. megalocarpa, in the N. Y. Bot. Gard. Herb.), Colorado Springs 

 (Porter in 1873), Ute Pass (Porter in 1873), Manitou (without indication of collector, in 1885, 

 Mulford in 1892). Wyoming; Horseshoe Park (Nelson 5053), Plumbaga Canyon (Schueburt 

 in 1893). Utah (Tracy in 1887), Salt Lake City (Jones in 1880), City Greek Canyon (Jones 

 1914, Leonard 250 and in 1883). Montana; Belt River (Williams 220). New Mexico; Lincoln 

 Co. (Wooton & Standley 3488, 3959), Balsam Park (Ellis 221, 224). 



Cuscuta denticulata Engelmann 



[Figures 46, 83 and 146] 



C. denticulata Engelmann, Amer. Nat. 9:348, 1875. — Hillman, Nev. Agr. Exp. Sta. Bull.. 



No. 15, fig. 5, 1892. 



Stems very slender. Flowers glabrous, about 2 mm. long, pentamerous 

 subtended by one to three denticulate, ovate-lanceolate, acute bracts, 

 one to several in scattered glomerules; calyx lobes orbicular, obtuse, 

 denticulate, deeply divided, overlapping, enclosing the corolla tube; 

 corolla campanulate, becoming urceolate in fruit; lobes ovate, oval or 

 slightly oblong, somewhat overlapping, about equalling the tube, spread- 

 ing to reflexed; scales denticulate, about reaching the anthers, oblong-ovate, 

 bridged at about the middle; anthers oval, shorter than the corolla lobes; 

 about equalling the filaments; styles shorter than the small conic ovary; 

 stigmas small. Capsule globose, conic, bearing the withered corolla at 

 the apex, mostly one- or infrequently two-seeded; seed about 1 mm. long, 

 light brown, globose-ovoid; hilum small. The embryo is thickened into 

 a large round knob at the plumule? end. 



Type locality: St. George, Utah. Range: Southern Utah, Nevada 



and California. 



Specimens examined: United States: Utah; St. George (Parry 205, the type, in the 

 Engelmann Herb.). Nevada; Esmeralda Co. (Schockley 443), Reno (Curran in 1888, Hillman 

 in 1891), Pyramid Lake (Curran in 1883, without indication of collector, in 1883). California; 

 The Needles (Jones in 1884, Rose 12074), San Bernardino Mts. (Parish 3230, 3231, 3236), 

 Mojave Desert, Tehachapi Pass (Abrams & McGregor 505), Palmdale (Abrams & McGregor 

 522), San Diego Co. (Orcutt in 1898), Barstow (Brandegee in 1909), San Bernardino Co. 

 (Parish 2436). 



