(383 ) 
1. CERASUS. Cuerry. 
1. CERASUS ARIDA Greene, Proc. Biol. Soc. Wash. 18: 57. 1905. 
Type locality: “Borders of the desert at eastern base of the 
San Bernardino Mountains.” 
Distribution: The cherry referred to this species occurs spar- 
ingly in the Transition Zone of the San Gabriel, San Bernardino 
and Cuiamaca Mountains. Considerable variation occurs in the 
specimens examined, and it is evident that a great deal of field 
study must be given to the western cherries before they are under- 
stood. The specimens from Strawberry Peak have narrow, oblan- 
ceolate, acutish leaves, which are pubescent and somewhat glan- 
dular on the lower surface. They also differ in their prominent 
approximate veins. 
Specimens examined: Lytle Creek Canyon, altitude 1725 meters, 
Hall 1471; near Strawberry Peak, San Bernardino Mountains, 
Abrams &§ McGregor 727; South Peak, Cuiamaca Mountains, 
Abrams 3943; Green Valley, San Bernardino Mountains, Abrams 
€F McGregor 734; San Jacinto Mountains, Hasse 5680, 1263; 
San Bernardino Mountains, altitude 2180 meters, Parish 3320. 
2. PADUS. CHOKE CHERRY. 
1. Papus pEMIssa (Nutt.) Roem. Syn. Rosifl. 87. 1847. 
Cerasus demissa Nutt. in Torr. & Gray, Fl.N.Am.1:411. 1840. 
Prunus demissa Walp. Rep. 2: 10. 1843. 
Padus virginiana demissa Schneider, Handb. Laubholzk. 1: 642. 
1906. 
Type locality: “Plains of the Oregon towards the sea, and at 
the mouth of the Wahlamet.” 
Distribution: Washington and Idaho to southern California. 
In southern California there is considerable variation in pubes- 
cence. The Cuiamaca specimens are glabrous except for pubes- 
sence along the mid-vein, thus approaching very closely P. melano- 
carpa of the Rocky Mountains and Great Basin. Upper Sonoran 
and Transition. 
Specimens examined: Mount San Antonio, altitude 2700 meters, 
Abrams 2697; Swartout Canyon, San Gabriel Mountains, Hall, 
June, 1899; Abrams &F McGregor 639; North Baldy, San Gabriel 
Mountains, Abrams &F McGregor 620; Cuiamaca, Abrams 3828; 
“summit of the cordillaries east of San Diego,” Parry, June, 1850. 
