M. TRECUL'S DISCOVERIES. 259 



more generally, limited patches of copse and thicket are met 

 with at intervals in these plains. The Smilax rotundifolia, a 

 species of sarsaparilla, with round leaves and sarmentous stems ; 

 the Rhus toxicodendmrn, a shrub with a very poisonous juice ; 

 and the Asimina triloba, a plant bearing nutritious fruit, are, 

 with a few other subfrutescerit species, the denizens of these lonely 

 localities. Annual or perennial plants abound in the prairies, and 

 attain there a considerable development, especially in the more humid 

 districts. The plains bordering on the Swan's Marsh, situated upon 

 the upper course of the River Osage, nourish a great number of species, 

 as elegant as they are varied. As in our own meadows, the Graminese, 

 the Cyperacea3 (or Sedges), the Leguminosse, and the Composites 

 the latter especially are very extensively diffused. But, in contrast 

 to the majority of our species, their representatives are in general of 

 remarkable dimensions, with flowers of extraordinary splendour, and 

 most of them have been naturalized in our British gardens. 



The American prairies, again, like the meadow-lands of Europe, 

 are alternated with dry, gravelly spaces, marshes, swampy angles, and 

 wooded tracts. It is curious to trace a certain likeness between the 

 genera which inhabit these localities in both continents. Thus, 

 M. Trdcul, who explored, in 1848 and 1849, nearly the whole of the 

 State of Missouri to the foot of the Rocky Mountains, Louisiana, 

 Texas, and a part of Northern Mexico, discovered in the vicinity of 

 the Swan's Marsh, Water-Plantains (Alisma), Sagittarias, and 

 Nymphreas, in the inundated districts ; Characese their tubular 

 branches incrusted with carbonate of lime bladder-plants, and the 

 beautiful floating Naiadacese, in deeper pools and stagnant watei-s ; 

 and the Lythracese (or Loose-Strife tribe) on the banks of the brook- 

 lets. But the commonest aquatic plant in these morasses, and that 

 which conceals, so to speak, all the other plants proper to such 

 localities, is the NelumHum calophyllum, with its rose-coloured 

 blossoms ; its seeds and rhizomes are eaten by the natives. 



The vast plains of Missouri are sufficiently fertile. Among the 

 plants most abundant in somewhat damp places we must notice 



