1200 CONTRIBUTIONS FROM THE NATIONAL HERBAEIUM. 



Woody vine ; leaflets obovate, elliptic, or lance-ovate, 1 to 4 cm. long, obtuse 

 to acuminate; sepals in fruit 3 to 3.5 cm. long; corolla about 5 cm. long; 

 seeds densely pubescent. 



7. Operculina palmeri (S. Wats.) House, Bull. Torrey Club 33: 502. 1906. 

 Ipuinoea paJmeri S. Wats. Proc. Amer. Acad. 24: 68. 1889. 



Sonora and Sinaloa ; type from Guaymas, Sonora. 



Woody vine; leaflets linear-lanceolate, 9 cm. long or less, acute at base; 

 sepals in fruit 4 cm. long ; corolla about 6.5 cm. long ; seeds densely pubescent. 



8. Operculina platyphylla (Fernald) House, Bull. Torrey Club 33: 502. 1906. 

 Ipomoea palmeri platyphylla Fernald, Proc. Amer. Acad. 33: 90. 1897. 

 Type from Acapulco, Guerrero. 



Stems suffrutescent ; leaflets elliptic or obovate ; sepals in fruit 3.5 cm. 

 long; corolla 7 cm. long. 



9. Operculina tuberosa (L.) Meisn. in Mart. Fl. Bras. 7: 212. 1869. 

 Ipomoea tuierosa L. Sp. PI. 160. 1753. 



Campecbe. Central and South America, West Indies, and Old World tropics ; 

 type from Jamaica. 



Plants glabrous, climbing over trees ; leaves mostly 7-lobate, 5 to 12 cm. long, 

 the lobes acuminate, entire; sepals in fruit as much as 6 cm. long; corolla 4 

 to 5.5 cm. long; seeds densely pubescent. 



10. Operculina dissecta (Jacq.) House, Bull. Torrey Club 33: 500. 1906. 

 Convolvulus dissectus Jacq. Obs. Bot. 2: 4. 1767. 



Ipomoea sinuata Ortega, Hort. Matr. Dec. 84. 1798. 



Merremda dissecta Hallier, Bot. Jahrb. Engler 18: 114. 1894. 



Sinaloa to Coahuila, Tamaulipas, San Luis PotosI, and Oaxaca. Florida and 

 Texas; West Indies; Central and South America. 



Stems chiefly herbaceous; leaves mostly 5-lobate, the lobes 2 to 8 cm. long, 

 deeply lobate ; sepals in fruit about 3 cm. long ; corolla 3.5 to 4 cm. long ; seeds 

 black, glabrous. 



11. Operculina omithopoda (Robinson) House, Bot. Gaz. 43: 414. 1907. 

 Ipomoea omithopoda Robinson, Proc. Amer. Acad. 27: 183. 1892. 

 Operculina roseana House, Bull. Torrey Club 33: 500. 1906. 

 Operculina angustiloba House, Bull. Torrey Club 33: 501. 1906. 

 Ipomoea megacarpa T. S. Brandeg. Zoe 5: 218. 1905. 



Operculina omithopoda megacarpa Robinson, Proc. Amer. Acad. 51: 530. 

 1916. 



Sinaloa to Tamaulipas, Veracruz, Yucatdn, and Chiapas; type from Las 

 Canoas, San Luis PotosI. 



Stems chiefly herbaceous ; leaves mostly 5-lobate, the lobes linear to ovate 

 or rhombic, entire or lobate, usually acute or acuminate ; sepals in fruit about 

 1.5 cm. long; corolla 4 to 5 cm. long; seeds glabrous. 



In the typical form the lobes of the leaves are linear. The more common 

 form with broad lobes is O. omithopoda megacarpa (T. S. Brandeg.) Robinson. 



12. Operculina pectinata House, Muhlenbergia 5: 69. 1909. 

 San Luis Potosi and Oaxaca; type from Lagunas, Oaxaca. 



Stems chiefly herbaceous ; leaves 4 to 7 cm. long, long-acuminate, truncate at 

 base, coarsely pectinate-dentate or lobate; sepals 12 to 14 mm. long; corolla 

 3.5 to 4.5 cm. long. 



