CONTENTS. 



Harvey Monroe Hall, A Botanical Survey of San Jarhilo Mountain. 



(Pages 1-140, Plates 1-14.) 



I.- 



II. 



-Introduction. page 



Selection of Sao Jacinto Mountain 3 



Region covered and collections made 3 



Collections made by others 5 



-General Features of San Jacinto Mountain. 



Position 6 



Topography 



Soil and climate 



Geology 



8 

 10 



III. 



IV 



-Plant Distribution on San Jacinto Mountain. 



The life zones 10 



The Upper Sonoran Zone 12 



The Transition Zone 13 



The Canadian and Hudsonian Zones ^. 15 



The Alpine Zone 16 



The phytogeographic formations 16 



The chaparral formations 17 



The forests 19 



The undergrowth •... -6 



The meadows -7 



The riparian formation 30 



The pond formation 31 



The crest formation 32 



The factors affecting plant distribution on San Jacinto 



Mountain 34 



Altitude, temperature, and moisture 34 



Slope exposure • 34 



Desert winds 38 



Rock surface, avalanches, and land slides 40 



Water courses 41 



The battle of the factors 4'2 



A comparison of montane and desert conditions 44 



-Origin and Affinities of the San Jacinto Flora. 



The boreal element 47 



The austral element 50 



The presence of Arizonan and New Mexican Species 50 



-Catalogue of Species Collected In or Above the Ykllow 

 Pine Belt 



VI.— Index. 



51 

 133 



LIBRARY 

 NEW YORK 

 BOTANICAL 



UARUBN 



