25 ON THE GENUS ERIOGONUM. 



bitus, in order to prevent the possibility of excluding the 

 present genus^ ^* Leaves generally alternate, rarely ver- 

 ticillate, furnished at their base with sheathing stipulae, 

 (in Eriogoniun obsolete or none!) laminae of the younger 

 Jeaves rolled under, stem for the most part herbaceous^ 

 sometimes arborescent."* 



The ,better to understand the genus Eriogonum I shall 

 now proceed to the description of the 3 species which 

 have, to the present time, been exclusively discovered 



* This order now contains the following genera. 1st. Coceolobay — all the 

 species trees or shrubs. The Coccoloba pubescens of the tropics becomes a 

 tree from 60 to 80 feet high, with extremely hard wood and enormous orbi- 

 cular leaves. 2d. Mraphaxist of which there are two species, both shrubby, 

 one with spiny branches, in Media and Siberia, the second a native of the 

 Cape of Good Hope. 3d. Polygonum^ oi \i\\\c\\ there are two shrubby species, 

 and upwards of fifty others which are herbaceous, and several with twining 

 Stems. 4th. Polygonella of Michaux, a small and extremely branching shrub, 

 HO where in the United Sates more abundant, and occurring, indeed, in scarce- 

 ly any Qther place but the sterile sand hills round Wilmington, in North Cai'o« 

 lina. It is referred to the genus Polygonum as P. polygamum by Ventenat, but 

 appears to be a distinct genus, having almost the seed and fruit calix of Ru- 

 Ttieoc. 5th. Brwuchia cirrhosa a single species, being a scandent shrub, com- 

 mon to the Bahama islands, and the Southern parts of the United States, its 

 northern limits as far as 1 have been able to ascertain, appear to be the south- 

 ern border of Savannah river. I have found it near Ebenezer bridge, 25 miles 

 above Savannah in Georgia, further to the south, and particularly around 

 Kew Orleans, it is extremely abundant. The flowers are produced in branch, 

 ing panicles, disposed in numerous fasciculi, the calix is tubular and ventri- 

 ccse, 5-parted, rather ringent, and angular, membranaceously complanate, and 

 attenuated towards the peduncle, which is extremely slender. The seed, which 

 Is solitary, as in the rest of the order, is inclosed by the persistent calix, which 

 becomes coriaceous, and suberose, with the lacinise then a little reflected.— 

 There is no capsule, as described by Persoon, a simple seed with a double 

 coating as in all the Polygonece, terminated by three short styles, each having a 

 3-lobed stigma, the seed is conic and triquetrous, the angles acute above, ob- 

 literated below. The perisperm is farinaceous, distinctly 3-lobed, and the 

 lobes again semibifid, the corculum is inverted, the seed lobes are flat and 

 erect, linear-oblong, generally immersed in the perisperm, sometimes only re- 

 garding one of the lobes; the radicle is exserted beyond the perisperm, touching 

 i^\e base of the styles. The character of an inverted corculum, given as one of 

 t|je generic distinctions of the pr^isent genus, is consequently of no importance, 



