THE FLORA OF THE PINE BELT OF THE SAN ANTONIO 

 MOUNTAINS OF SOUTHERN CALIFORNIA 



I. M. JOHNSTON 



Pomona College, Claremont, California 



Continued 



PLATANACE.E 



Platamis racemosa Nutt. Ranging a short distance up into the pine belt, but 

 characteristic of lower altitudes. 



ROSACEA 



Sericotheca concolor Rydb. Common in dry exposed places in the Canadian Zone 



and not uncommon on dry, open, sandy canon floors of the Upper Transition 



Zone. In both Icehouse Canon and Middle Fork Lytle Creek it was found at 



as low as 6500 ft. alt. (Nos. 1270, 1566, 1570, 1582, 1696.) 

 Amelanchier alnifolia Nutt. Icehouse Canon at 7250 ft. alt. and at 7000 ft. alt. 



in both Cold water Fork Lytle Creek and Prairie Fork. The first station is 



on a dry rocky place on the canon floor while the other stations are both in 



springy ground. 



Our plants have the glabrous hypanthia and sepals of the segregate, A. 



recurvata Abrann. A. venulosa Greene, another segregate of A. alnifolia, is 



reported from Swartout Valley by Abrams (Bull. N. Y. Bot. Gard. 6:382, 



1910). (Nos. 1388, 1539, 1681, 1711.) 

 Heteromeles arbutifolia Roem. Enters the pine belt in Prairie Fork and in San 



Antonio Canon. 

 Drymocallis viscida Parish. Common in moist ground in the Transition Zone. 



(Nos. 1410, 2062, 2068, 2072.) 

 Drymocallis lactea (Greene) Rydb. Locally very abundant in a marsh in a small 



side canon of Prairie Fork. Upper Transition Zone, alt. 7000 ft. (No. 2066.) 

 Cercocarpus betulaefolius Nutt. Frequent in the lower parts of the pine belt. 

 Cercocarpus ledifolius Nutt. As a shrub at its lower limits and a tree in its upper 



ranges, this species extends throughout the Transition Zone and well into 



the Canadian. (No. 1485.) 

 Rubus leucodermis Dougl. Occasional in moist rocky ground in the Transition 



Zone. (No. 1462.) 

 Rubus parviflorus Nutt. "In moist shady places in the San Antonio and San 



Bernardino Mountains in the pine belt." Ace. Abrams, Fl. Los. Ang. • 



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