> PENTANDRIA. MONOGYNIA. 123 



iVom the summit of the tube, alternating with 

 the segments of the corolla. Stigmata 3. Cap- 

 sule S-celled, 3-valved, many-seeded. 



Species. 1. D. lapponica. A small cespitose herb 

 with the aspect of Sedum, and the leaves crowded around 

 the root; (as In most alpine plants), peduncles scapiform, 

 1-flowered. A\\\cd to Aretia. 2. barbulata. (Pyxidan- 

 THERA, Mich.) A small sempervirent cespitose herb, 

 with erect surculi, and sessile, terminal flowers; anthers 

 somewhat g-lobular, caudate at the base, opening trans- 

 versel}'. Probably distinct from the present genus. ^ 



Excluding the Pyxidanthera, there exists but a single 

 species of Diapemia, common to the Lapponic alps, and 

 the White Hills of New Hampshire. 



190. CONVOLVULUS. L. (Bind-weed.) 



Calix 5-parted. Corolla campanulate, plaited. 

 Stigmas 2. Cajmile £ or 3-celled, cells 2- 

 seeded. 



Lactescent and mostly twining herbs; peduncles axil- 

 lary or terminal, one or many-flowered, flowers mostly bi- 

 bracteate. A few of the tropical species are shrubby. 



Species. 1. C. tenellus. (G. trichosanthes, Mich. C. 

 Sherardi, Pursh.) 2. aquaticns. 3. Sepium. 4. stans. 5. spU 

 thcmea. 6. paradoxus. P. (3, 4, 5, and 6, are referred by 

 Pursh to Calystegia of R. Brown, a genus not suflEi- 

 ciently characerised, without Mr. P. has suppressed 

 something important in abridging it.) 7. Batatas. (Sweet 

 Potatoe. 'cultivated. No where indigenous probably in 

 America; but spontaneous in India.) 8. obtusilobus. 9 sa- 

 gittifoHns. 10. panduratiis. \\. arvensis. 12. pitrptireus. 13. 

 macrorhizo7i. (Supposed to have been the Cjalapa of the 

 shops by Persoon and others, but as a medicine proves 

 inert, and on the authority of Dr. Baldwyn might rather 

 be used as an article of diet!) 14. tamnifoUus. 



This extensive genus of near 140 species appears to be 

 almost equally divided betwixt India and the warmer re- 

 gions of America, there are also many species in Africa, 

 some in Australasia, only 3 in England, and an equally 

 small number in the North of Europe, yet there are not 

 species entirely wanting in Siberia; some of those within 

 the tropics are remarkably splendid, whilst others in 

 colder countries are obscure and inconspicuous weeds 

 usually occupying neglected wastes. 



