;38 



Trees of Southern California. 



[ZOE 



PHYTOGRAPHIC RELATIONS. 



The region here under consideration presents three distinct 

 floras; that of the mountains, that of the desert, and that of the 

 district between the main range and the sea coast, which may be 

 called the intramontane. Adopting Dr. Merriam's phytographic 

 areas, the mountain flora belongs to the Nevadan subzone, the 

 desert to the Sonoran proper, and the intramontane to the Cali- 

 fornian, or in a more general view the whole territory may be 

 regarded as a part of the great Sonoran life area, into which pro- 

 jects, along the axis of mountains, a narrow arm of the Boreal. 

 These relations become evident from a tabulation of the trees, 

 and would be further enforced b)'^ an examination of the distribu- 

 tion of the shrubs and herbs. 



Acer glabnim 



Pnimis emarginata mollis 



Coj'niis Nuttallii 



Sa lix fa vescens 



Querais Kelloggii 



Castanopsis clnysopliylla 



Pinus Lambertiana 



MOUNTAIN AREA. 



Pimis albican lis 

 Pituis pondc70sa 

 Pinus Jeffrey i 

 PifiKS Co niter i 

 Piny.s Miirrayaiia 

 Abies concolor 

 Libocedrtis decurrens 



This zone is connected with the intramontane flora by a belt 



of Psendotsuga macrocarpa, and with the desert flora by a belt of 



Ce?rocarpus ledifoliiis and Juniperns oceidentalis. Negiindo Cali- 



foi)iica and Piuus tubcrculata also occur on the edge of this zone. 



INTRAMONTANE AREA. 



Rha m n us Calif or n ica 

 R. Californica totnentella 

 Acer inacrophyllum 

 Negundo Calif ornicuni 

 Pruitus ilicifolia 

 Pninus demissa 

 Cercocarpus parvifolius 

 Hetero m eles arbu ti folia 

 Sambucus glauca 

 Um bellu la ria Ca liforn ica 



Juglans rupestris 



Quercus chrysolepis 



Quei'cus agrifolia 



Qtierctis lobata 



Alnus rhombifolia 



Populus Fremonti Wisliseni 



Salix laevigata 



Salix lasiolepis 



Salix lasiajidra land folia 



Platanus racemosa 



