NO. 2 GENTRY : LAND PLANTS 69 



In low and middle elevations from southern Baja California and 

 central Sonora south into Central America, especially along canyon 

 water courses. It is the most common and widespread fig tree in western 

 Mexico. Elmore notes it as growing on the island ''in good red dry 

 volcanic soil with aerial roots from overhead branches." Johnston ( 1931 ) 

 reports that these broad large trees are a favorite haunt of the untended 

 sheep so numerous on Socorro Island. He attributes this to their desire 

 for shade. They may also be attracted by the edible fruits dropping 

 upon the ground and which are a favorite source of food for both wild 

 and domestic animals in Mexico. People eat them in times of hunger, 

 but generally as a source of food they are not desirable. 



This island collection shows some minor differences in leaf vena- 

 tion from that of typical mainland material, but due to lack of flores- 

 cence it cannot be more critically compared. Its affinities are obviously 

 close to that of F. cotinifolia, and in spite of the apparently long isola- 

 tion of the Socorro Island population, it is unlikely that it would show 

 more than varietal distinction. Ficus is an old genus, known from the 

 Cretaceous. 



Nyctaginaceae 



BoERHAAViA CARiBEA Jacq., Obs. Bot. 4:5, t. 84. 1771. 



Braithwaite Bay, Socorro Island, March 18, Elmore C7y Cll, elev. 

 100 feet, in crevices of basaltic rocks where there was sufficient dis- 

 integrated rock to form soil. 



A low viscid perennial herb with small dark purple flowers widely 

 distributed in the American tropics. The specimens are fragmentary 

 remains of plants indicating an earlier period of florescence. It normally 

 flowers in the summer and fall. 



AlZOACEAE 



Sesuvium portulacastrum L., Syst. Nat. ed. 10, 2: 1058. 1753. 



Sulphur Bay, Clarion Island, March 16, Elmore BIO, clay soil around 

 old lagoon, flowers pink. 



Widely distributed in brackish soils in the American tropics, but 

 not abundant on the adjacent Mexican coast and not known from other 

 Revilla Gigedo Islands. 



Leguminosae 



Phaseolus atropurpureus sericeus Gray, Proc. Am. Acad. Sci. 

 5:156. 1861. 



Sulphur Bay, Clarion Island, March 16, Elmore B2, many plants 

 on upper beach, flowers dark red. 



