36 ILLINOIS BIOLOGICAL MONOGRAPHS [126 



reaching beyond the middle of the tube; filaments sometimes as long as the 

 anthers; ovary globose-ovoid to conic. Choisy's figure of the flowers of 

 this variety does not correspond with the specimen of the type number 

 examined, showing the division of the calyx too deep, etc. 



Type locality: Mexico. Range: Central and southern Mexico. 



Specimens examined: Mexico: (Berlandier 822, the type of C. stylosa, a specimen 

 of the tj'pe number in the Engelmann Herb.). Federal District; Valley of Mexico (Pringle 

 6574). Puebla (Nelson 2014). Vera Cruz; Vera Cruz (Parry & Pahner in 1877), Orizaba. 

 (Miiller 1260), Zacuapan (Purpus 5745, 7564, 7775). Hidalgo; Zimapan (Galeotti 1412). 

 Mexico; Toluca (Andrieux 214), Guadaloupe, Valle de Mexico (Bourgeau in 1866), Valle de 

 Cordova (Bourgeau in 1866). Chiapas; Comitan (Linden). 



Cuscuta macrocephala Schaffner, n. sp. 

 [Figures 19 and 108] 

 C macrocephala Wilh. Schaffner in herb. 



Stems coarse. Flowers glabrous, 5-6 mm. long, pentamerous, on 

 pedicels as long as or shorter than the flowers in scattered cymose clusters; 

 calyx deep, texture thick and rather fleshy, nearly covering in most speci- 

 mens the cylindrical corolla, somewhat angled below the sinuses; lobes 

 short, broadly ovate, lobed, overlapping; corolla lobes short, broadly ovate, 

 obtuse, overlapping, lobed, upright to slightly spreading; scales deltoid- 

 oblong, shorter than the corolla tube, shallowly fringed, bridged at, or 

 somewhat below, the middle; stamens sessile; anthers oval; styles much 

 longer than the globose or slightly conic ovary; stigmas broad (about 

 .8 mm.), globular or slightly conic. Capsule circumscissile, globose, the 

 withered corolla carried at the apex; seeds about 2 mm. long, one to four 

 in each capsule, oval, angled ; hilum a narrow transverse line. 



This species somewhat resembles C. corymhosa grandiflora, from which 

 it differs in the corolla not bulging between the stamen attachments, in 

 the somewhat cordate lobes and their greater overlapping, and in the more 

 prominent scales and larger stigmas. 



Type locality: Culiacan, Sinaloa, Mexico. Range: Central and 

 northern Mexico. 



Specimens examined : Mexico : Sinaloa; Culiacan (Schaffner, without date or number, 

 the type, in the N. Y. Bot. Gard. Herb., Brandegee in 1904). Tamaulipas; Victoria (Palmer 

 52). Lower California; San Jos6 del Cabo (Brandegee in 1897), San Bartolome (Brandegee 

 409), Todos Santos (Brandegee in 1890), LaPaz (Palmer 141). 



Subsection leptilobae Engelmann 



Cuscuta § Leptolobae Engelmann, Trans. Acad. Sci. St. Louis, 1:485, 1859. 



Flowers mostly smaller; calyx lobes acute to acuminate; corolla lobes 

 mostly as long as or longer than the tube — in the last three species some- 

 what shorter; styles slender, longer than the ovary. Chiefly of Mexico, 

 the West Indies and the southern and western United States. 



Key to the species 

 Calyx about equalling or exceeding the corolla (shorter in C. deltmdea). 

 Flowers ordinarily at least 2.5-3 mm. long; calyx lobes overlapping. 



