188 ANNALS NEW YORK ACADEMY OF SCIENCES 



Mexico : Chihuahua, between Colonia Garcia and Pratt's ranch, below 

 Pacheco, E. W. Nelson 6276, 1899 (type, sheet No. 369993 — ^). 



^ 9. Ipomoea lenis sp. nov. 



A dwarf, perennial, shrubby plant with thickened, woody base; stems erect, 

 10-30 cm. tall, densely woolly or silky pubescent with white hairs; leaf-blades sessile, 

 oblong, obtuse at both ends, 6-10 mm. long, 2-4 mm. broad; flowers solitary in the 

 upper axils and often crowded; peduncles 5-8 mm. long; sepals equal, ovate-lanceo- 

 late, obtuse, 5-6 mm. long, the outer ones silvery- pubescent; corolla fuimelform, 5-6 

 cm. long, blue, glabrous, the limb 4-5 cm. broad, 5-lobed. 



Mexico: Zacatecas; Near Berriozobal, E. W. Nelson 3889, July 8, 

 1896 (type, sheet No. 266883 — N, dupl. G). 



10. Ipomcea leptophylla Torr. in Frem. Rep. 95. 1845. — Emory, 

 Rep. pi. 11.— Morris in Plant World 7: pis. 5 & 6.— Small, Fl. 

 Southeastern U. S. 964. 1903.— Roth. Bot. Wheeler 205. 1878. 



Convolvulus Caddoensis Buckley in Proc. Phila. Acad. 1862: 6. 1862. 



Type locality: Upper Platte. 



Distribution: Dry soil, plains of South Dakota and southeastern 

 Montana to Texas and New Mexico. 



3. Arborescentes. Erect, woody, arborescent or shrubby perennials, 

 often several m. tall; leaf-blades oblong-ovate to narrowly or triangular- 

 ovate, rounded, truncate or subcordate, rarely subsagittate at the base; 

 sepals coriaceous, obtuse; corolla white, rarely pink or purple; capsules 

 narrowly ovoid, or oblong ; the coma of hairs on the seeds very long. (Ipo- 

 mcea Sect. Orthipomosa, § Arborescentes, Choisy in DC. Prodr. 9: 358. 1845. 



Seeds with black coma on all surfaces. 



Twigs and leaves puberulent or glabrous; leaf-blades 

 cordate-sagittate or truncate. 



Leaf-blades oblong, acuminate. 11. /. fistulosa. 



Leaf-blades ovate, short-acuminate. 12. I. glahriuscula. 



Twigs and leaves densely canescent; leaf -blades ovate- 

 cordate. 13. /. nicaraguensis. 

 Seeds with white coma only on the dorsal angles. 



Corolla and sepal densely woolly without. 14. /. murucoides. 



Corolla and sepals pubescent or glabrous, not woolly. 

 Foliage more or less densely pubescent; veins promi- 

 nent beneath on the blades. 



Leaf-blades ovate, cordate. 15. /. arborescens. 



Leaf-blades, oblong, rounded at the base. 16. /. cucrnavacensis . 



