BOTANICAL. INFORMATION. 35 



feet of thickness, in the water-rent banks of the Missouri at 

 Council Bluffs. 



We have now arrived again at the sandy barrier of Lower 

 Platte Valley, which consists most probable the decomposed 

 strata of carboniferous sandstone, formerly overlying the 

 horizontal limestone of the Missouri, which we saw last as 

 the bed of Grasshopper River, a small stream, tributary to 

 the Kanzas River, about 120 miles S.W. from the mouth of 

 the Platte. 



We will now retrace our steps, and follow these hills 

 and mountains up again to their respective centre, for the 

 purpose of taking a view of the Vegetation.* 



Commencing at that place, we are at the southern boundary 

 of the Triticum Missouricum, a glaucous Graminea spread 

 over plains and mountains of Missouri and Oregon terri- 

 tories, down to nearly the edge of the coast of the Pacific. 

 A little further, and we have already left behind us the 

 last fertile lands of the Missouri, and stand on the sandy 

 barriers of Platte Valley again. (Passed through the belts of 

 (Pentsfemon grandjflorum, P. dubium, (Enothera, 268.) 



From hence, following the sand-hills and escarpments 

 * It may safely be asserted that much more is known about the vege- 

 tation of Oregon and California than that of this mountain region. Most 

 botanists have not the means to equip expeditions of their own, and 

 are obliged to attach themselves to caravans of traders, missionaries, 

 or emigrants, who move onward without loss of time, passing rapidly 

 most striking portions, to stop, perhaps, for a day or so only, at the 

 least interesting. The great number of new plants which Captain 

 Fremont found on the Wind-river Mountains, prove sufficiently that he 

 must have been the first explorer. Not less a rich collection of new 

 plants could be made by an exploration of the " Black Hills/' difficult and 

 perilous though the undertaking would be. From that quarter we may yet 

 look for a number of species of Eriogonum, perennial Bartonias, prostrate 

 Phacee ; dwarf Cruciferous plants, as Leavenworthiee, Thlaspi, as well as 

 Stanleyas, ligneous (Enotkerte ; Sides, Thermice, Lygodesmia, &c, &c, and 

 some new species of Pines and Juniperus may also be expected. For 

 Finns fiexilis, mentioned lower down, I have the authority of Dr. Mersh ; 

 it is said to be the most slender of all the pines, producing merely polea 

 of about 60 feet high, with short twisted branches. I myself saw it only 

 at a distance, growing in small groups. 



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