BOTANICAL IN FORMATION. 303 



from the level loamy plains. The sand, for the most part, 

 covers solid basalt, which appears as if cast over immense 

 tracts of land, but is for the most part naked. On the sand 

 some scanty pines scarcely maintain, life, except in ravines, 

 and towards rivers, as well as in the immediate neigh- 

 bourhood of the basalt masses. A basalt of a closer grain, 

 but likewise shapeless, appears in series of low, rounded, 

 conic heaps, as if baked, its surface scaling off in small 

 conchoidal fragments, like flints. These range parallel with 

 the great masses, and generally protrude out of the sand. 

 Towards the Columbia River these plains become more 

 wooded as the elevation lessens, and their sides are some- 

 times again walled with the before- mentioned pseudo-co- 

 lumnar basalt; the more so as they approach to the cotes 

 (several thousand feet high) of the Columbia River. The 

 most western portion of this region is again saline sandy 

 desert, borne on coarse gravel, and in part again on pseudo- 

 columnar basalt. 



General characters of the vegetation ■' — Scanty woods ofPinus 

 ponderosa on the sandy rocky tracts, but large trees are found in 

 depressions and plains of less height, and in narrow river-val- 

 leys ! Celtis, Rhus, and Corylus first appear on the west side ! 

 — Sambucus and Symphoricarpus abundant in river-valleys ! — 

 Ribes and Philadelphus on rocky banks ! — Brilliant colours cha- 

 racterize the flora of the herbaceous plants ! — Chief habitat of 

 Clarkia pulchella, Lewisia rediviva and Collomia elegans, cha- 

 racterizing the whole of this region ! — Small-flowering Ona- 

 grece, abundant in the genera Epilobiwn, Clarkia, Euchari- 

 dium, Oenothera, and Gaura! — Umbellifera abundant, chiefly 

 in the genera Ferula, Eryngium, Osmorrhiza, and Peuceda- 

 num .'—Boraginea abundant in Pulmonaria, Rochelia, Onos- 

 modiwn, Cynoglossum y Hydrophyllum, Phacelia ! —Polemonia- 

 ce<e in Polemonium, Collomia, Cantua ! — Lewisiea in Lewisia ! 

 Pedicular es, in Orabanche, Orthocarpus, Castilleja ! — Ciclw- 

 racetB in Hieracium, Lygodesmia, Troximon, Crepis, Sonchus — 

 InuletE ; Pyrrocoma,Gnaphalium, Antennaria, Espeletia, Chry- 

 sopsis, Inula ? Calycadenia .'—Asterea ; Erigeron, Diplopappns, 

 Chrysocoma, Aster, Solidago !—Helwnthea> ; Hymenopappris, 



