572 Part IV. Chapter 3. 
Salizaria mexicana. Opuntia rutila, Cereus Engelmanni, Mammillaria phellosperma, Opuntia echino- 
carpa appear in flower. The large class of compositous, chenopodiaceous and perennial Erio- 
goneae come forward in the latter part of May. 
River Bottom and Meadow-Formation. The water courses are marked by 
the presence of Salix longifolia, S. cordata, Rosa blanda, Shepherdia argentea 
Prunus demissa and Ribes aureum with Populus tremuloides on the stream 
banks in the upper canyons. 
On the banks of streams in the lower canyons are Ribes irriguum, Sambucus glauca, Cornus 
pubescens (= C. occidentalis) or more rarely Crataegus rivularis, Alnus incana, while on the rich 
moist hillsides are Wyethia amplexicaulis, Lophanthus urticaefolius, Geranium Richardsonii. The 
banks of the Truckee River, as it runs through Truckee Valley, are covered with a dense growth 
of Populus balsamifera, P. trichocarpa, Salix argophylla, S. lasiolepis, S. padophylla and Alnus 
hombifolia, according to KEnnEDY2). Popu i 
Cieuta vagans, Mimulus Langsdorfii, Prunus demissa, Rosa Woodsii and Ribes aureum, Above 
the valley grow Acer glabrum, Alnus tenuifolia, Amelanchier Cusickii, Ribes cereum. 
Along the river bottoms in southwest Colorado grow Crataegus coccinea, Salix lasiandra, 
S. cordata var. Mackenziana, Oeccasionally clumps of Rhamnus californica, also occur with Rhus 
aromatica (= R. canadensis), Shepherdia argentea, Prunus demissa, Ribes aureum, Berberis Fend- 
leri, while Pachystima myrsinites earpets the ground under the taller shrubs. Ceanothus Fendleri 
is common in open spots on rocky slopes. C. ovatus also occurs. In the basin of the Green 
River, an extension of the arid Great Basin into the mountains, are groves of Populus angusti- 
folia beneath which trees grow Glyeyrrhiza lepidota, Symphoricarpos racemosus, Rosa Fendleri 
while Salix longifolia, S. amgydaloides, Pirus sambucifolia, Rhus canadensis var. trilobata, Ame- 
lanchier alnifolia also are found. — The marshes and margins of the lakes ma green 
with Scirpus maritimus, Juncus balticus, Equisetum hyemale, Sporobolus (Vilfa) depauperata, 
Agropyrum -repens. 
The swamps in the Truckee Valley which are characterized by a dense growth of Typha 
latifolia, Sagittaria latifolia, Sparganium simplex intergrade with the meadows where are found, 
according to the soil and the amount of water, Carex ampullacea, C. aquatilis, C. lanuginosa, 
Eleocharis arenicola, Juncus, Seirpus and Trifolium spinulosum. 
The following plants are to be classed as aquatic and meadow species3): Nasturtium 
(Roripa) Ilyratum, Selinum Kingii, 
Tolmieana (= I missouriensis), Carex vesicaria, C. aemathorhyncha (= C. filiformis), Gentiana 
affınis, Epipactis gigantea, Zygadenus Nuttallii, Deschampsia danthonioides, Valeriana edulis, 
Aster simplex (= A. paniculatus), Gratiola- virginiana Typha latifolia, Potamogeton natans, 
P. pectinatus, Alisma plantago, Sagittaria variabilis (= S, latifolia), Eleocharis acicularis, E. pal- 
ustris, Elatine americana, Panicum erus-galli, Ceratophyllum demersum, Schollera graminea, Spar- 
ganium eurycarpum &e. 
Desert Sinks Formation: The 
the desert or to desert sinks ar 
Jatus (widely distributed) 
var. fruticosa, Distichlis s 
the characteristic vegetation. 
I) PARRY, C. C.; Bot. observ. in southern Utah in 1874. See Bibliography. 
2) KenneDy, P. B.: Botanical Features around Reno, Muhlenbergia III: 17—32. 
3) WATSoN: loc. eit. p. XXX, 
Rn ER. SEN er 
Seirpus nevadensis, Carex Watsoni, Tillaea angustifolia, Iris 
A AR a SE SR 
- a Ge 
‚plants which are confined ‘to alkaline spots in 
€ Spirostachys occidentalis, Sarcobatus vermicu- 
associated with Selicornia herbacea, Suaeda depressa 
en 
TEN 
picata and Spartina gracilis which together form 3 
1 
De 
Ve Er 
5 
