478 



RHAMNACEAE 



Loes. — Marin Co., C. F. Baker 3162; Calistoga, sw. of, on Rebecca ranch grade, Jepson 

 4022; Franz Valley grade from Calistoga, Jepson 13,990. 



Rcfs.— Ceanothus cuneatus Nutt.; T. & G. Fl. 1:267 (1838); B. & W. Bot. Cal. 1:104 

 (1S76) ; Trel. in Gray, Syn. Fl. r:416 (1897) ; Jepson, Fl. W. Mid. Cal. 257 (1901), ed. 2, 255 

 (1911), Man. 623, fig. 622 (1925). Bhamnus ? cuneatus Hook. Fl. Bor. Am. 1:124 (1830), typo 

 loc. headwaters of the Willamette ("Multnomak") River, Ore., Douglas. Var. ramulosus 

 Greene, Fl. Fr. 86 (1891), type loc. Santa Cruz Mts., Greene; Jepson, Man. 623 (1925). 



27. C. rigidus Nutt. Coast Ceaxothus. Shrub 3 to 6 feet high, rigidly and 

 intricately branched with numerous often unequal branchlets; leaves rather 

 crowded, the blades euneate-obovate, mostly retuse, of medium thickness but firm, 

 soon nearly glabrous on both surfaces, the apical half finely dentate or quite entire, 

 2 to 5 lines long, nearly sessile; stipules conspicuously warty; flowers bright blue; 

 capsules not lobed, 3 lines in diameter, provided with 

 prominent horns 



Dry rocky or sandy slopes, 25 to 2000 feet : near 

 the coast from Marin Co. to Santa Barbara Co. Feb.- 

 Apr. 



Loes. — Mt. Tamalpais, Jepson 6808; Monterey, Jepson 

 2993; Purisima Hills near Lompoc, Jepson 11,926, The root 

 tubercles on the root system in this species were first observed 

 by us on Mt. Tamalpais in 1908 (cf. fig. 237). 



Refs.— Ceanothus rigidus Nutt.; T. & G. Fl. 1:268 

 (1838), type loc. Monterev, Nuttall; Torr. Bot. Mex. Bound. 

 45, pi. 9 (1859) ; Paxton's Fl. Gard. 1:74, fig. 51 (1851) ; Jep- 

 son, Fl. W. Mid. Cal. 258 (1901), ed. 2, 255 (1911), Man. 623 

 (1925). C. verrucosus var. rigidus K. Bdg. Proc. Cal. Acad, 

 ser. 2,4:207 (1894). 



28. C. jepsonii Greene. Musk-bush. Rigid erect 

 shrub 4 to 5 feet high; branchlets short, rigid, with 

 gray bark; leaf -blades elliptic, coriaceous, green and 

 glabrous above, tomentulose-areolate beneath, spiny- 

 toothed, undulate-margined, or somewhat infolded longitudinally, 4 to 10 lines 

 long; warty stipules small; flowers white or blue, exhaling a musky odor; pedicels 

 2 to 3 lines long; capsules 2 to 2i/^ or 3 lines broad, with horns 1^/2 to 2 lines long. 



Dry hills and fiats, 1500 to 2500 feet : southeastern Mendocino Co. and north- 

 eastern Lake Co. to Napa and Marin Cos. Apr. 



Geog. note. — A species of limited distribution, it is most common in the Napa Range and 

 Miyakma Range where its colonies form an important part of the chaparral. It is killed com- 

 pletely by chaparral fires and regenerates only from seed. 



Loes. — Red Mt., se. of Ukiah, Jepson; ridge betw. Bear and Indian valleys. Lake Co., Jepson 

 8976; Lower Lake (ridge east), Jepson; betw. Adams Sprs. and Glenbrook, Lake Co., Jepson; 

 Mt. St. Helena (Middleton grade), Jepson 10,377; Howell Mt., Jepson 2451, 6589; Chiles Creek 

 hiUs, Jepson 6263, 9069. 



Var. purpureus Jepson. Branchlets brownish or reddish; leaf -blades thick, orbicular, 1 inch 

 long or less, somewhat undulate, coarsely and pungently toothed all around; warty stipules 

 large; flowers large, purple; pedicels 5 to 7 lines long. — Southern Napa Range; Guerneville 

 (leaves nearly plane), 



Refs. — Ceanothus jepsonii Greene, Man. Reg. S. F. Bay 78 (1894), type loc. San Geronimo, 

 Marin Co.; Jepson, Fl. W. Mid. Cal. 258 (1901), ed. 2, 255 (1911), Man. 624, fig. 623 (1925). 

 Var. purpureus Jepson, Man. 624 (1925). C. purpureus Jepson, Fl. W, Mid, Cal, 258 (1901), 

 type loc, near Mt. George, Napa Co., Jepson 14,027; ed. 2, 255 (1911). 



29. C. prostratus Benth. Mahala Mat. Prostrate plants, the branches thickly 

 matting the ground, often rooting and forming dense mats 2 to 15 feet broad; 

 branchlets often reddish, at first pubescent; leaf -blades green on both surfaces, 

 glabrous or finely flocculent-pubescent beneath, thick and firm, euneate-obovate, 

 coarsely and pungently 3-toothed at the apex, and often with 1 or 2 similar teeth 

 on each side mostly above the middle, 4 to 9 lines long (or even to 1^4 inches long) ; 

 flowers blue ; capsules globose, not lobed, 3 to 4 lines broad, with 3 large wrinkled 

 horns and 3 intermediate crests. 



Fig. 237. Ceanothus rigidus 

 Nutt.; root tubercles, X 1%. 



