278 BOTANICAL GAZETTE [APRIL 
shelf just east of Fallen Leaf Lake), and Salix lasiandra form the 
superior stratum, and beneath them grow Alnus tenuifolia, Rubus 
parviflorus, and Cornus pubescens as undershrubs, while the herbs 
most frequently found are Carex rostrata, Allium validum, Habe- 
naria leucostachys, Thalictrum sparsiflorum, Cicuta vagans, and 
Heracleum lanatum. The lowest stratum, made up of delicate 
herbs for the most part, shows Listera convallarioides, Polygonum 
Douglasii, Kelloggia galioides (which is also found in the forest), 
Galium bifolium, and Anaphalis margaritacea. 
Scrub (chaparral) becomes of considerable importance on dry 
sunny slopes in the Tahoe Upper Transition; the principal species 
are Amelanchier alnifolia, Cercocarpus ledifolius, and on sandy 
benches Artemisia tridentata, the last being present as a consider- 
able factor in all the zones below the true alpine. Among these 
shrubs one finds Lilium Washingtonianum, Eriogonum nudum, 
Collomia tinctoria, Mimulus Breweri, Mimulus leptaleus, and 
Mimulus Torreyi. 
When the relief becomes too sharp and the soil covering too 
scanty for chaparral shrubs, there is found a flora of rocky outcrops 
and benches, composed of small perennials and annuals. Here 
grow Eriogonum Douglasii, Oxytheca spergulina, Heuchera rubes- 
cens lithophila, Apocynum androsaemifolium, Gilia pungens, 
Cryptanthe affinis, a form of Monardella odoratissima (M adronella 
pallida Heller), Adenostegia tenuis, Chrysopsis hispida, and Serico- 
carpus rigidus. 
The meadow formation is well developed along Truckee River; 
about Donner Lake, and where the Upper Truckee enters Lake 
Tahoe both east and west of Tallac. Almost exclusively it is 4 
wet meadow, since the dry meadow is speedily invaded by trees 
and grows into the climax forest. Such an invasion and young 
forest growth is now taking place just back of Tallac, Pinus Jeffrey! 
seedlings being the chief entrants. On the wet meadow are Spar- 
ganium simplex, many carices (Carex lanuginosa here below its 
average level, Carex nebraskensis), Juncus nevadensis, Verairum 
californicum, Urtica gracilis, Delphinium decorum patens, Tri- 
folium cyathiferum, with Trifolium pratense and Trifolium repens 
as immigrants into the meadows about Donner Lake, Hypericum 
