Great Basin Elements, 
Xerophyte formation. 
Astragalus Nuttallianus, lentiginosus, dentatus, 
Gilia inconspicua. [scapoideus, albicaulis, 
Eriogonum gracile, plumatella, deflexum, in- 
atum, cernuum, angulosum, Wrightii. 
Chorizanthe brevicornu, rigida. 
Tetradymia spinosa. 
Anisocoma acaule. 
Stephanomeria (Ptiloria) minor (= S. tenuifolia). 
Glyptopleura marginata. 
schscholtzia californica. 
Eritrichium mieranthum, angustifolium. 
Piptocalyx (Krynitzia) eircumseissus, 
Pentstemon Palmeri. 
Abronia fragrans, turbinata. 
Townsendia strigosa. 
Aristida purpurea. 
Myosurus aristatus. 
Lepidium flavum, Fremontii, alyssoides. 
Thysanocarpus elegans. 
Capsella divaricata. 
upinus pusillus. 
Hosackia (Lotus) Heermanni. 
Psoralea lanceolata. 
Malvastrum Munroanum ‘(= M. coccineum). 
Sida hederacea. 
Cymopterus' montanus, pterocaryum. 
Amsinckia lycopsoides. 
Nicotiana -attenuata. 
The following alkaline species have been found, so far as known only 
within the limits of the Great Basin and, therefore, form an endemic ele- 
ment: 
Arabis longirostris, Thelypodium sagittatum, Cleomella plocasperma, Astragalus pterocarpus, 
Ivesia (Horkelia) Kingii, Aster Nuttallii, Aplopappus (Pyrrocoma) tenuicaulis, Crepis Andersoni, 
Lyeium Andersoni, Erythraea Nuttallii, Monolepis_pusilla, Atriplex (Obione) phyllostegia, A. (O.) 
pusilla, Kochia prostrata, Spirostachys (Halostachys) occidentalis, Fimbristylis thermalis. But five 
Species of aquatic plants can be considered to be peculiar to the G 
margin of lakes and streams, marshes, etc. though the localities in which they are found may 
often be to a considerable extent alkaline: Nasturtium (Roripa) lyratum, Selinum Kingii, Pota- 
mogeton marinus, Scirpus nevadensis, Carex Watsoni*). 
The remaining plants of the valley flora including a large proportion of 
endemic species are those which occupy the drier sandy or gravelly portions 
of the valleys and the foothills and are consequently subject to a greater 
eXtreme of heat and drought. Many of them are low, or dwarfed, annuals, 
often varying much in size and habit with the circumstances of their growth, 
usually starting with the rains of autumn, flowering in early spring and has- 
'ening to a quick maturity. With the first heats of summer, they vanish. 
Others are stouter and hardier, more or less woody biennials, or perennials, 
“Pringing from bulbs, roots, or rootstocks and persisting longer until July 
under the Protection of the shrubs which remain. 
A large number of (one third) peculiarly desert species, are strictly con- 
fned to the Great Basin and on the whole southern, quite a large number 
Xtending into the Mohave and Colorado deserts and a few into New Mexico 
°7 even western Texas. Many of the endemic species of the drier valleys 
and foothills are described in Part IV, Chapter II. In the absence in ._ 
el Any forest growth to indicate the limit of arborescent vegetation, it 15 
u Warson, SERENO: Botany United States Geological 
Exploration of the Fortieth Parallel. 
ce King: 1871. General Report. ne 
