168 TEKTANDRIA, DIGTNIA. 



flowered? Petals oblong'-oval, white, externally cinereoxit- 

 greeii, near tlie points. Lepanthiura white, -luiih'mt tube! 

 jjcrfectly sessile. PoUinlum short, lobes even, angularly 

 iniracted, bt^les 2, long-. flAB. From Carolina to Florida. 

 Specimen collected by Dr. Baldwin, from whom I receiv- 

 ed it, under the name of ».?. cinej^ea. 



f f Leaves scattered, or verdcillate. 



18. rerticilluta. Stem erect, often branching", marked 

 ■witii pubescent lines, leaves smooth, narrow linear, crowd- 

 ed, mostly verticillate; tube of the lepanthium con- 

 spicuous, segme?its very short, awns lonjj- and falcate. 

 19. longifolia. Flowers greenif,!). — In Carolina, Ceorgia, 

 Illinois, and Louisiana iN early allied to A. viridijlora 

 of Piirsli, if not the same.f 20. *hiJuiglnosa. Plant very 

 low, decumbci.t, and partly lanuginous; leaves ovate, scat- 

 tered, umbell solitary, tenninid. Obs. 4 to 6 inclies high; 

 root tuberous, flowers greenish. iM} specimen was very 

 imjicrfect. iHAB. About 30 miles below the confluence 

 of White river with the Missouri, on dry and gravelly 

 hills. It is the only species wliich I met with in the up- 

 per part of Louisiana. 2\. txiberosa. 



The United States already afford about half as many 

 species of this genus as the rest of the world, thus far 

 explored. The tropical paits of America, according to 

 Persoon, produce only 5 species. At the Cape of Good 

 Hope there are 9; 5 in India and Ce}lon; 1 in Persia, 

 besides A. -np-iaca, 1 in China, 2 in Arabia Feiix, 1 in 

 Dauria, and 1 in Sil^eria. The 2 European species ap- 

 pear eitiiCr re Terrible to Ci^nanchiim or to const.tute a dis- 



I This plant, according to R. l^rowm, is a species of hi.s genus 

 Gomphocnrpns, if the mere abserice of the corniculum or arista, 

 usually arising out of the coi.cave loljes of ti.e lepanthium, can 

 be considered of generic importance; tiie single denture or 

 "auricle" as it was called b\ Linnjeus in his descrijjtion of .is- 

 .:!epiasfri{ticosa{Co?up/iGcar'pufifniticosKS, of It. iirown) termi- 

 nating either bide ol' tlie lobe, we have already shown to be 

 eonmion to several genuine species of Asciepias, (such as .^. 

 sm^aca, A .phiiolaccoidts, &.C. and remarkably in A. cinerea.') The 

 armature of the foilicle, its being smooth ov muricated, is like- 

 wise an unimportant character, tliere being indubitable species 

 of Asch'piiis, both witli one and the other. Tbere arc also spe- 

 cies of Gonolobus with costate, murlc:;te, and smooth tblliclcs. 



It is nothing less than a duty to the public, which prompts 

 me to these observations on the ingenious labours of a man so 

 eminently indefatigable, so accurate, and so justly celebrated. 

 It is also highly probable, that this very revision has already 

 been made by Mr, II. Brjwn liimseif. 



