XXVI. ROSA.^CE2E I PU'RSHIA. 297 



20ft. to 30ft. Introduced in 1759. Flowers white ; May. Drupe dark 

 purple ; ripe ?. 



This tree Michaux considers as one of the most beautiful vegetable pro- 

 ductions of the southern parts of the United States ; and it is generally se- 

 lected by the inhabitants to plant near their houses, not only on this account, 

 but because it grows with rapidity, and affords an impenetrable shade. Pursh 

 describes it as a handsome evergreen shrub, resembling C. lusitanica ; but he 

 says nothing of the flowers, which, from the figure in Michaux, from which 

 ours was copied, appear to be almost without petals. Seeds are frequently 

 imported from America, and abundance of young plants reared ; but, as they 

 are rather tender, and, north of London, would require the protection of a 

 wall, they are very seldom seen in British gardens. The largest plant which 

 we know of is in Hampshire, at Swallowfield, where, in 1833, it formed a 

 bush 10ft. high, with a head about 12ft. in diameter, flowering and fruiting 

 occasionally. Culture as in C. virginiana, but north of London it requires the 

 protection of a wall. 



Sect. II. SPIRJEE'IE. 

 GENUS VI. 



PU'RSH/,4 Dec. THE PURSHIA. Lin. Syst. Icosandria Monogjnia. 



Identification. Dec. in Trans, of Linn. Soc., 12. p. 157. ; Prod., 2. p. 541. ; Lindl. in Bot. Reg. 

 t. 1446. ; Don's Mill., 2. p. 517. 



Synonyme. Tigarea Ph. Fl. Amer. Sept., 1. p. 333., not of Aublet. 



Derivation. Frederick Pursh first characterised the only known species in his Flora America, 

 Septentrionalis, and named it Tigarea tridentata. The generic name, however, having been 

 preoccupied by Aublet, De Candolle has named the present genus after Pursh himself. 



Gen. Char. Calyx 5-cleft ; lobes ovate, obtuse. Petals 5, obovate. Stamens 

 about 25, rising with the petals from the calyx. Carpels 1 2, ovate oblong, 

 pubescent, tapering into the style at the apex, at length opening by a lon- 

 gitudinal chink. Seed 1, inserted in the base of the carpel. (Don's Mill.) 



Leaves simple, grouped together, cuneate, 2 3-toothed at the apex, 

 stipulate or exstipulate, deciduous. Flowers yellow. Shrub, of which 

 there is only one species known. 



j* 1. P. TRIDENTATA Dec. The 3-toothed-kaved Purshia. 



Identification. Dec. in Lin. Trans., 12. p. 157. ; Prod., 2. p. 541. 



ie. Tigarea tridentata Ph. Fl. Amer. Sept., 1 . p. 333. t. 15., not of Aublet. 

 ngs. Ph. Fl. Amer. Sept., 1. 15. ; Bot. Reg., 1. 1446. ; and our Jigs. 487, 488. 



Spec. Char., $c. Leaves obcuneate, 3- 

 dentate, crowded on the points of the 

 shoots, hairy above, and tomentose 

 beneath. Flowers terminal on short 

 peduncles. (Ph. Fl. Amer.) A spreading 

 shrub. North America, on pastures 

 by the river Columbia. Height 2 ft. to 

 3 ft. Introduced in 1826. Flowers 

 yellow ; July. Carpels ?. 



487. P. tridentita. Almost the only shrub to be seen 



through an immense tract of barren sandy 

 soil, from the head source of the Missouri, to the Falls of the Columbia. The 

 plants in the London gardens were all killed in the winter of 1837-8. 



