CONVOLVULACEJE. 



form from cordate to linear, all pointed, and lobed, or angular and 

 downy. Peduncles axillary, downy, many-flowered. Flowers large, 

 white. Bractes oval, concave, velvety, deciduous. Ovary seated on a 

 large glandular disk. Stigma 2-lobed. Capsules involved in the dry 

 calyx, absolutely 4-sided, 2*celled, opening at the apex by a kind of 

 operculum. Seeds round, black, 1 in each cell. The fresh bark of 

 the root rubbed up with milk is used in India as a purgative. About 

 6 inches in length of a root as thick as the little finger is reckoned a 

 dose. 



807. I. macrorhiza Mich. Fl. Bor. amer. i. 141, supposed 

 to be the Convolvulus Jalapa Linn., a plant inhabiting 

 the sandy soil of Georgia and Carolina, with white insipid 

 farinaceous roots weighing from 40 to 50 Ibs., is asserted by 

 Elliott (sketch i. 253.), to possess no purgative properties what- 

 ever. Dr. Baldwin assured him that he had administered 6 

 drachms of the powdered root without effect, and that in fact it 

 contains little or no resin, but like the Batatas consists chiefly 

 of saccharine and farinaceous matter. 



808. I. pandurata. Convolvulus panduratus Linn, sp.pl. 219. 

 Barton mat. med. i. t. 23. Common in North America in 

 sandy fields and by fences from Canada to Florida ; " Mecha- 

 meck" of the Indians. 



Root very large, 2 or 3 feet long and as thick as the arm, of a yellow- 

 ochre colour. Stem downy. Leaves on long stalks, broadly cordate, 

 entire, acuminate, slightly repand. Peduncles many-flowered, cymose, 

 longer than the petioles. Corolla large, campauulate, white, dull purple 

 towards the base. Stamens white, the length of the tube. The 

 powdered root acts like rhubarb ; it requires to be given in larger doses 

 than jalap. It has an American reputation as a remedy for calculous 

 affections, and in cases of gravel. 



809. I. Purga Wenderoth in lift, ad Zuccar. Schkcht. in 

 Linncea viii. 515. I. Schiedeana Zuccarini Plant, nov. fasc. 

 i. 293. t. 12. I. Jalapa Nutt. in Am. journ. med. sc. v. 300. 

 Purga of the natives of Jalapa. Laschachne, Tetonpactle 



Mexicans On the eastern declivity of the Mexican Andes 



near Chiconquiaco and near San Salvador on the eastern face of 

 the Cofre de Perote, at an elevation of about 6000 feet above 

 the sea. The mountains near Orizaba. 



Root tuberous, fleshy, with numerous roundish tubercles. Stem 

 smooth, brownish, very slightly rough. Leaves stalked, the first hastate, 

 the succeeding ones cordate acuminate, mucronate, smooth. Peduncles 

 axillary, 2-flowered, twisted, the lennth of the corolla. Sepals obtuse, 

 mucronate, smooth. Corolla purple, with a long somewhat clavate 

 tube, and an undulated limb, with 5 plaits. Filaments smooth ; unequal, 

 longer than the tube of the corolla ; anthers linear, projecting. Stigma 

 capitate, deeply furrowed. Capsule 2-celled ; cells 2-seeded. From 

 the statements of Dr. Schiede, and others, confirmed by an unpublished 

 letter in the possession of the Horticultural Society of London, from 

 Don Juan de Orbegozo, a pupil of Cervantes, residing at Orizaba, it 



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