Vol.1] Hall. — Botanical Survey of San Jacinto Mountain. 33 



and well developed, as a result of the vigorous winds of these 

 regions and the great depth to which they are obliged to pene- 

 trate in order to secure a sufficient amount of moisture, while 

 the slender stems, which bear leaves provided with some device for 

 the checking of excessive transpiration, die back each winter. 

 Among the commoner species may be mentioned Eriogonum 

 saxatile, Silene ParisJm, Gilia pungens, and Hieraceum horridum. 



Following now this formation along the ridges to the highest 

 point on San Jacinto Mountain, we notice that the characters of 

 the vegetation as described above undergo no radical change, but 

 that they become more and more intensified as the altitude 

 increases. As the summit, which has an altitude of 10,805 feet, 

 is neared, it is seen to be covered with large rocks, the soil 

 being scant and composed entirely of decomposed granite; while 

 at places, especially on the north side, it drops off in steep 

 canons, the walls and bottoms of which are of almost solid rock. 

 These canons, continuing to descend very rapidly for over 7000 

 feet, soon reach altitudes of a more temperate climate, l)ut in 

 their upper portions small banks of snow remain throughout the 

 summer, and along their margins a few alpine species of plants 

 find the conditions favorable to their growth. On the other 

 three sides of the peak the descent is much less rapid and here 

 are found quite a number of boreal plants, the most conspicuous 

 of which are the stunted specimens of the Limber and Murray 

 Pines. Other species grow mainly in sheltered places, often in 

 enclosures which are quite surrounded by rocky walls, and are 

 all hardy, thick-rooted perennial herl^s and shrubs. 



Siiice the floras of isolated mountain peaks are always of 

 interest, a list of the species found growing on the summit of 

 San Jacinto Mountain, that is, between 10,700 and 10,805 feet 

 altitude, has been prepared. 



PLANTS OP THE SUMMIT OF SAN JACINTO MOUNTAIN. 



Aquilegia truncata (alpine form) Pinus flexilis 



Carex Preslii P. Murrayana 



Castaneachrysophylla Ranunculus Esehscholtzii 



Draba corrugata Ribes cereum 



Heuehera rubeseens R. lacustre moUe 



Holodiscus discolor dumosa Silene Parishii 



Monardella odoratissima Spraguea umbellata (alpine form) 



Oxyria digyna Trisetum subspieatum 



Pedieularis semibarbata 



