1160 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Corolla tube 7.5 to 12.5 cm. long 3. M. macrosiphon. 



Corolla tube 3 to 5.5 cm. long 4. M. hypoleuca. 



1. Macrosiplionia hesperia Johnston, Proc. Calif. Acad. 12: 1125. 1924. 

 Southern Baja California ; type from Carmen Island. 



Leaves short-petiolate, orbicular or reniform-orbicular, 1.5 to 3 cm. long 

 and broad, rounded at apex and apiculate, truncate or subcordate at base, 

 densely velutinous-pilosulous above, beneath very densely pilose but scarcely 

 tomentose ; follicles 6 to 8 cm. long, 3 to 4 mm. thick, densely puberulent. 



2. Macrosiphonia brachysiphon A. Gray, Syn. Fl. 2^: 83. 1878. 

 Northern Sonora, near the boundary. Southern Arizona. 



Plants suffrutescent, 60 cm. high or less, puberulent ; leaves oblong to broadly 

 elliptic, 2 to 3 cm. long, acute to rounded at apex ; flowers fragrant ; corolla 

 white, the tube 2.5 to 5 cm. long ; follicles 6 cm. long or more. 



3. Macrosiplionia macrosiphon (Torr.) Heller, Muhlenbergia 1: 2. 1900. 

 Echites macrosiphon Torr. U. S. & Mex. Bound. Bot. 158. pi. 43. 1859. 

 Macrosiphonia herlandieri A. Gray, Syn. Fl. 2': 83. 1878. 



Chihuahua to Tamaulipas, San Luis Potosi, and Durango. Western Texas; 

 type collected along the Rio Grande. 



Low shrub ; leaves short-petiolate, mostly oval, 2 to 4 cm. long, acute to 

 rounded at apex, truncate or rounded at base, tomentulose or glabi'ate above ; 

 flowers white, sweet-scented; corolla limb 4.5 to 6 cm. wide; follicles 6 to 10 

 cm. long. " Flor de San Juan" (Durango, Coahuila) ; " hierba de San Juan" 

 (Coahuila, Tamaulipas). 



4. Macrosiphonia hypoleuca (Benth.) Muell. Arg. Linnaea 30: 452. 1860. 

 Echites hypoleuca Benth. PI. Hartw. 23. 1839. 



Echites suaveolens Mart. & Gal. Bull. Acad. Brux. 11: 356. 1844. 



Echites lanuginosa Mart. & Gal. Bull. Acad. Brux. 11: 357. 1844. 



Macrosiphonia lanuginosa Hemsl. Biol. Centr. Amer. Bot. 2: 316. 1881. 



Sinaloa to Chihuahua, San Luis Potosi, Hidalgo, and Puebla ; type from 

 Aguascalientes. 



Shrub, 1 meter high or less ; leaves linear to oblong-ovate, 2.5 to 7 cm. 

 long, rounded to acute at apex, green above but puberulent, the margins often 

 revolute ; flowers white, very sweet-scented ; corolla limb usually 6 to 7 cm. 

 wide; follicles 9 to 16 cm. long. "Flor de San Juan" (Sinaloa, Guanajuato, 

 San Luis Potosi, Jalisco, Durango); "rosa de San Juan" (Sinaloa, Oaxaca, 

 Guerrero, Durango); " giiirambo " (Guerrero); "hierba de la cucaracha " 

 (San Luis Potosi) ; "San Juan" (Durango) ; " maravilla silvestre " (Sinaloa). 



The pulverized plant, mixed with sugar, is said to be useful for poisoning 

 cockroaches. Palmer reports that in San Luis Potosi and Durango a decoc- 

 tion of the plant is employed for pains in the stomach, toothache (applied hot 

 to the tooth), and externally for inflamed eyes. 



The species shows great variation in size of flowers and in leaf breadth, 

 but the leaves vary greatly upon the same plant, the lower being often much 

 broader than the upper ones. 



15. RHABDADENIA Muell. Arg. in Mart. Fl. Bras. 6*: 173. 1860. 



Scandent shrubs; leaves opposite, petiolate; flowers large, in few-flowered 

 racemes ; calyx 5-parted, eglandular ; corolla f unnelform, the tube cylindric, the 

 throat long-campanulate ; anthers oblong, obtuse, short-appendaged at base; 

 follicles terete, linear-fusiform ; seeds with a terminal tuft of hairs. 



