8 CONTENTS. 
The Zonal distribution of Washington plants—Continued. Page. 
Origin of the Arid Transition flora_...........- ©.) 8-8 51 
The Californian element. ...........__..____. oo eee 51 
The Rocky Mountain element...............__________._.... a 52 
The Columbia Basin element._._...__.___...--.---.-... 8 52 
Comparison of the Humid and Arid Transition floras. _.._.._..._.___. 53 
The Canadian zone __.--_.--. ©. 5-68 58 
The Hudsonian zone__._._...-.....---- 2-2 - 60 
The Arctic zone ___._---_-. 2-22 222 62 
Regions of peculiar botanical interest... _.......____.______........... 65 
The Olympic Mountains___------- 68-8 65 
The Columbia Gorge __._-.-.-----.-- 6 eee ee 67 
Klickitat County .-.. _. 2022-222 68 
Mount Stuart and the Wenache Mountains oe ee 68 
The Blue Mountains--..0 © © -88) 71 
Plants known to occur only in Washington. __._______.___......__. ~o eee 7 
Plants which probably will be found to occur in Washington ____.._..___. 75 
Annotated catalogue of the species of vascular plants of Washington_____ 76 
Addenda _..-.-.-.0 2-22-2222 80 ee 613 
Bibliography -...-....------- 2-20-28 eee 615 
Geographic index.-...----. ©) =. eee wae ne ee eee eee ee eee 619 
ILLUSTRATIONS. 
PLATES. 
Facing page. 
PuLaTE I. Giant cedars (Thuja plicata) _.. __.._.__....._._....... Frontispiece 
II. Topographic map of Washington... _....- =. 20 
III. Characteristic vegetation of the bluffs along Puget Sound. .____- 21 
IV. Steamboat Rock, in the Grand . oulee _____.___-_.._____ 25 
V. Rainfall map of Washington _. Wee ee eee 28 
VI. Sagebrush plains in Yakima County... -.....--.._._._... a 36 
VI. Forest of red fir (Pseudotsuga mucronata) in Washington ______- 41 
VIII. Characteristic view in a moist forest .-..... _....__.___.___... 41 
IX. Pasture-like gravelly prairies of Pierce County... _________. 42 
X. Lupinus rivularis on the gravelly prairies in Pierce County ___. 43 
XI. Prairie of bunchgrass (Agropyron spicatum) on the Horse 
Heaven Hills, Klickitat County_. a 48 
XII. Range lands near White Stone Lake, Okanogan County __ ~ eee eee 48 
XIII. View in a coulee near Lyons Ferry __.-.----.-2 2-8. 49 
XIV. Forest of yellow pine (Pinus ponderosa)......-__________... 50 
XV. Forest of yellow pine (Pinus ponderosa)_.._.______.__..._.__._. 50 
XVI. Forest of hemlock (Tsuga heterophylla)... ._--___..._. 58 
XVII. Subalpine firs (Abies lasiocarpa) in Paradise Valley, Mount 
Rainier ------ 2-22) ee 60 
XVIII. Vegetation of the Gorge of the Columbia River___.__.___. 67 
XIX. Bunchgrass (Agropyron spicatum) growing on basalt outcrop- 
pings ----- 2 ee 146 
XX. White hellebore (Veratrum californicum) Woe eee eee 196 
XXII. Iris missouriensis______- wee eee eee eee 202 
XXII. Lupinus ornatus in low meadows. near ‘Wenas ween ee eee eee 355 
MAP. 
Map showing the floral areas of the State of Washington __.________. In pocket 
