21(5 ROSACEAE 



Locs. — Coast Ranges: Stone Lagoon, lliiniholdt Co., Jep.son 9337a; Bridgevillc, Iluniboldt 

 Co., Tracy 7018; Mill Crock, Ukiali, Jcpsnn 4010; Conn Valley, Napa Range, Jcpson 10,314; 

 Fairfax, Marin Co., BioJctii; Nortonville, Contra Costa Co., Jepson 15,722; Berkeley Hills, Jep- 

 son 0G2S; Arroyo Grande, San Luis Obispo Co., Alice Kinrj. Sierra Nevada: Rough and Ready, 

 Nevada Co., Jepson 13,867; Auburn, BoUmdcr 4541; Columbia, Tuolumne Co., Jcpson 021)9 (the 

 last two spuis. with larger caly.x-lobes and densely pilose calyx-tube representing Aphanes macro- 

 sepala Rydb.) ; Jackson, Amador Co., Hansen; 5lariposa Co. foothills (Zoe 3:28). S. Cal.: 

 Mission La Purisima, Santa Barbara Co., Jepson 11,942; Prisoners Harbor, Santa Cruz Isl., 

 Mabel Peirson; Santa Ynez Mts., T. Brandegee ; Santa Catalina Isl., Davidson; San Bernardino 

 Valley, Parish <3813 ; San Uiego, T. Brandajce. 



Refs. — Alchkmilla arvensis Scop. Fl. Carn. ed. 2, 1 :115 (1772) ; Greene, Fl. Fr. G2 ; Jepson, 

 Fl. W. Mid. Cal. 284 (1901), ed. 2, 211 (1911), Man. 502, fig. 498 (1925). Aphanes arvensis L. 

 Sp. PI. 123 (1753), type from Europe. AlchcmiUa cuneifolia Nutt.; T. & G. Fl. 1:432 (1840), 

 type loc. Santa Barbara, Nuttall. Aphanes cuneifolia Rydb. N. Am. Fl. 22:380 (1908). A. 

 macroscpala Rydb. I.e., type loc. Wimer, Ore., E. W. Hammond 110. Alchemilla arve7isis var. glabra 

 Greene, Fl. Fr'. 62 (1891), type loc. Sacramento Valley. 



20. CERCOCARPUS IIBK. Mountain Mahogany 



Evergreen shrubs or low trees with spur-like branchlets and simple coriaceous 

 straight-veined leaves. Flowers from winter buds, solitary or fascicled, terminal 

 on the short branchlets. Calj'x consisting of a slender pedicel-like tube abruptly 

 expanded near the summit into a low-hemispherical cup, its lobes 5, small, these 

 and the cup deciduous from the persistent tube. Petals none. Stamens numerous, 

 borne in two or three rows on the calyx-cup. Pistil 1. Fruit a villous achene en- 

 closed in the persistent calyx-tube and surmounted by the very much elongated 

 twisted soft-hairy style. — Species 6, western North America. (Greek kerkis, a 

 shuttle, and karpos, fruit, in reference to the achene and its twisted tail.) 



Bibliog. — Schneider, C. K. Beitrag zur Kenntnis der Arten und Formen der Gattung Cer- 

 cocarpus Kunth (Mitt. Deutseh. Dendrol. Gesellsch. 14:125-129,-1905). Rydberg, P. A., Cer- 

 cocarpus (Bull. Torr. Club 41:497-503,-1914). 



Flowers solitary or rarely in pairs, sessile ; desert ranges. 



Leaves narrowly lanceolate, i/^ to 1 inch long 1. C. ledifolius. 



Leaves oblong, 2% to 5 lines long 2. C. intricatus. 



Flowers in 2 to 15-flowered clusters, shortly pediceled. 



Leaves obovate, cuneate at base ; clusters commonly 2 or 3-flowered. 



Flowers 3 lines broad; cismontane, abundant 3. C. betuloides. 



Flowers 1 to 1^/^ lines broad; San Diego Co 4. C. minutiflorus. 



Leaves ovate to elliptic ; clusters 4 to 9-flowered ; Santa Barbara Isls. 



Leaves glabrous or nearly so 5. C. alnifolius. 



Leaves white-tomentose beneath 6. C. trashiae. 



1. C. ledifolius Nutt. Desert IMahogany. Curl-leaf Mahogany. Shrub 

 or scraggy tree, usually 6 to 20 or sometimes 40 feet high; leaf -blades narrowly 

 lanceolate, entire with revolute margins, coriaceous, pale or rusty-pubescent below, 

 becoming glabrous and lustrous above, somewhat resinous, % to 1 inch long, with 

 a prominent midrib; calyx-tube in fruit 4 to 5 lines long, sessile; tail of achene 

 2 to 3 inches long. 



Arid slopes, flats, plateaux and caiion walls of ranges in and bordering the 

 deserts or arid interior, 4000 to 8600 feet : San Jacinto, San Bernardino and San 

 Gabriel mountains; Mt. Pinos; easterly summits and east slopes of the Sierra Ne- 

 vada from Kern Co. to Modoc Co., thence west to Siskiyou Co. North to Wash- 

 ington, east to Colorado. July- Aug. 



Field note. — Cercocarpus ledifolius is one of the more important woody species in the desert 

 ranges. In the White Mts. it occurs as pure well-developed colonies on the open slopes below the 

 Pinus flexilis belt. These colonies consist of shrubs averaging 7 to 10 feet high, the trunks mostly 

 8 to 12 inches in diameter at the ground, branching at or near the ground into many stems. In 

 Silver Canon it colonizes broad bands up and down the walls, conforming to the blue rock, or 

 where the walls, 1500 to 2000 feet high, are almost vertical it finds a favorite habitat on the ledges. 



On the abrupt east wall of the Sierra Nevada this species forms a belt between the altitudes 

 5000 and 8000 feet on the average. Individuals in this belt are frequently arboreous. Near 



