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Description of several New or Rare Plants which have lately 

 Flowered in the Neighbourhood of Edinburgh, chiefly in the 

 Royal Botanic Garden, By Dr Graham, Prof, of Botany. 



March 10. 183<>. 

 Poinsettia. 



Involucrum monopliyllum, androgynum, basi 5-Ioculare, extus appen- 

 diculatum, nectariferum. Flores pedicellati, nudi; masculi bifarjan* 

 in singulis loculis ordinati, monandri ; f oemiuei solitarii, gennen tri- 

 lobum, ovulum solitariam singulis lobis. 



Poinsettia pulcherrima. 

 Euphorbia pulcherrima, Herb. Willd. 

 Euphorbia Pbinsettiana, Buist MS. 

 Bescriftiok — Shruh erect, ramous; branches round, young shoots bluntly 

 4-angled, green, glabrous, hollow. Leaves scattered, occasionally opposite, 

 spreading, petiolate, ovato-elliptical, subacute, sinuated, veined, soft and 

 pubescent on both sides, bright green above, paler below. Petioles fur- 

 rowed above. Bracteae similar in shape to the leaves, but aggregated at 

 the extremities of the branches, and of splendid vermilion colour, paler 

 below. Cymes terminal, subtrifid. Involucres green, on short stout 

 erect footstalks articulated at the base, ovato-orbicular, toothed, marked 

 by five sutures on the outside, with which alternate on the inside five 

 falcate processes, beginning with narrow extremities at the mouth of 

 the involucre, and, adhering to this with their backs, become gra- 

 dually broader below, passing inwards, and attached to an elevation in 

 the centre, divide the lower part of the involucre into five distinct 

 cells, and supporting on their edges erect fimbriae, they divide the upper 

 part also, but less completely ; teeth of the involucre numerous, coloured 

 like the bracteae, woolly on the inner side, fringed at their extremities, 

 connivent. Appendage single on the outside of the involucre towards 

 the axis of the cyme, round, entire, peltate, folded in the middle, so as 

 appear 2-lipped, nectariferous. Male Flowers about 14, in two rows in 

 each loculament and arising from its base, erect, petiolate, naked, mo- 

 nandrous, mixed with chaffs (abortive male flowers?) which are woolly 

 at the apex, and occasionally tinged red there ; petiole colourless, as long 

 as the involucre ; filament red, at length hanging over the edge of the 

 involucre; anthers 2-lobed, lobea divaricated, so that those which are next 

 to each other in the two rows of stamens overlap, opening along their 

 outer sides; pollen yellow, granules round. Female Flower solitary, cen- 

 tral, petiolate, naked ; germen 3-lobed, each lobe emarginate ; style awant- 

 ing; ovule solitary in each lobe. These appearances I describe as I saw 

 them, but the female flowers were probably imperfect, none enlarged, pro- 

 jected beyond the involucre, or produced seed ; but after a while, a small 

 number of the male flowers in succession having been perfected and pro- 

 truded beyond the involucre, this became yellow, and the whole separated 

 at the articulation near the base of the footstalk. 

 By whom this truly splendid plant was communicated to Willdenow's Her- 

 barium, I am not informed ; but it was again discovered in Mexico by 

 Mr Poinsette, and sent by him to Charleston in 1828, and afterwards to 

 Mr Buist of Philadelphia, who has within a very few years brought to- 

 gether a choice collection of plants, equally creditable to his enterprize, 

 and promising as a point from which will be diffused a greater knowledge 

 of the vegetation of North America. From Mr Buist it was brought 

 by Mr James Macnab to the Botanic Garden, Edinburgh, and to several 

 other establishments in this country, in November 1834 : from the in- 

 formation communicated by him, it has since been imported into other 



