248 IOWA ACADEMY OF SCIENCE Vor. XXIX, 1922 
numerous species of the so-called lilacs, species of Ceanothus, 
members of the family Rhamniaceae. These have white or bluish 
colored flowers. I collected the following species in the region : 
Ceanothus thyrsif torus , C. cordulatus , C. cuneatus and C. prostra- 
tus. Some of the species are prostrate, others are erect. There 
are few twining plants, in the region. The only common species 
in the lower Merced valley is the California grape ( Vitis Cali - 
fornica). 
The California nutmeg ( Umbellularia Calif ornica) , with aro- 
Fig. 3. Yosemite Falls. In the foreground lodge pole, yellow pine, fir and cotton- 
wood. The blotches on the mountain sides are largely golden cup oak 
matic leaves, is abundant on the mountain slopes. Many other 
trees and shrubs, some of which will be referred to later, occur 
in the valley below the moraine at the lower end of the Yosemite. 
Flowing through the valley is Merced river. This valley is an 
old lake and is about seven miles long and a mile or so wide. It 
is for the most part now covered with trees, the remainder con- 
sisting of open meadows which have been spoiled by the intensive 
grazing. The beautiful meadows spoken of by earlier writers 
are a thing of the past. The moraine is situated between the 
famous HI Capitan and Bridal Veil Falls. El Capitan rises 3604 
feet above the floor of the valley. The Bridal Veil Falls are 620 
feet high, while the Yosemite falls are 1430 feet high. 
The most marked features of the floor of the Yosemite Valley 
from the standpoint of vegetation are the large and superb speci- 
