Great Valley of California. 281 
away is remarkable. The wide plain is covered with plants belonging to the 
following genera: Zupinus, Trifolium, Calandrinia, Platystemon, Eschscholtzia 
(notably the orange-flowerd Z. crocea), Baeria, Gilia, Nemopkhila, Allocarya, 
Bahia, Madia, Madaria, Burrielia, Chrysopsis, Pentstemon, Coreothrogyne, 
Phacelia, Grindelia, growing in close association and blending with the purples 
of Clarkia, Orthocarpus, Oenothera. The shallow streams and pools are edge 
with species of Eunanus and Bolelia. The tide of plant life reaches its maxi- 
mum from April fifth to twentieth. In one, two or three weeks more, the 
brilliant colors have faded and the vernal aspect is succeeded by the duliness 
and aridity of summer. June, July, August and September is the season of 
rest and sleep, of dry heat, followed in October by a second outburst of bloom 
at the very driest time of the year. Hemizonia virgata appears and carpets 
the ground remaining in flower until November, uniting with two or three 
species of Eriogonum, which continue the floral chain through December until 
the spring flowers appear again. 
In contrast to the Spring growth on the plains, the height of the season 
for the herbaceous growth of the river region is in September and October, 
when the landscape is as fresh and green as the landscape in April on the 
plains. Verdena hastata, Euthamia occidentalis, Aster Douglasii, Stachys albens, 
and Graphalium californicum are mere instances of decided color. Annuals 
are commonly four to five feet tall. 
Clearly the flora of the tule swamps is sharply demarcated from and older 
than the plains flora, for there is geologic and physiographic evidence that in 
addition to a subsidence of great recency to the extent of at least 378 feet at 
the mouth of the Sacramento River, flooding the lower portion of the valley, 
giving us the magnificent harbor at San Francisco '), there _. series of pre- 
ceding subsidences, followed by the deposition of sediments '). Er 
During this entire period of subsidence and sedimentation, the e = " 
Conditions were such in the brackish marsh areas along the Bar line ot t ss 
landlocked sea, now represented by the Great valley as to permit re ah 
of a marsh flora which still persists in similar situations at the present = 
Then too, the present marsh flora, closely related to that in eastern m 
Must have entered the region, when the divergences between the er 
western floras were still less pronounced and before ... - 
the later and present plains flora to occupy the now dıy ae caho BE 
There are also certain plants that are confined to the imme ze . n 
the ocean in southern California 3), either on the sand of the are — 
tida] Marshes or meadows. These are exhibited in the subjoined table. 
Br TER 
alt ia. Bulletin 
a 1) Lawson, ANDREW C.: The Geomorphogeny of the Coast of northern Californi 
Ueninent Geology University of California I: 241—272. 
2) See ante page 277. 
PR? ical Gazette XXXVI: 
sl Parısh, S.B.: A Sketch of the Flora of southern California. Botanıca 
260, 1903, 
