PEA FAMILY 



299 



calyx-tube oblique, the upper side low; upper lobes with one bristle, lateral lobes 

 commonly with 2 bristles each, the lowest lobe commonly with 3 bristles; corolla 

 purple or lilac, much longer than the calyx. 



Valley fields, 10 to 200 feet : Mendocino Co. to Santa Cruz Co. May. 



Biol. note. — Trifolium grayi is a rather localized endemic of which the known stations are 

 comparatively few. We believe it to be a mutant from T. barbigerum Torr. A similar mutant 

 from that species is T. lilacinum Greene, which is evaluated on the basis of its morphological 

 characters as a variety of T. barbigerum. The stem in T. grayi frequently exhibits a very re- 

 markable habit in that it branches in one plane. There 

 are, however, localities where the plant does not show 

 this habit. 



Loes. — Russian Gulch, Fort Bragg, Davy 6585; "^Mi^ H^JjsV? ^li 



Mendocino City, Bolander 4781; Fulton, Sonoma Co., 

 Mason; Mt. Olivet School, betw. Trenton and Mark 

 West, V. BlacTcney; Petaluma, Congdon; Pt. Eeyes, 

 Davy 6727; Potrero bottoms, San Francisco, Kellogg 

 4" Sarford 138; Santa Cruz, Anderson. 



Eefs. — Trifolium grayi Loja. Nuov. Giorn. Bot. 

 Ital. 15:189, t. 3 (1883), resting upon the folloAving. 

 T. barbigerum var. andrewsii Gray, Proc. Am. Acad. 

 7:335 (1868), type collected by Andreivs, the locality 

 not stated; also cited, Mendocino City, Bolander; Mc- 

 Der. N. Am. Sp. Trifolium 124, pi. 46 (1910) ; Jepson, 

 Fl. W. Mid. Cal. ed. 2, 226 (1911), Man. 541 (1925). 



14. T. microdon H. & A. Square-head 

 Clover. Stems erect or decumbent, % to 2 

 feet high, the branches usually slender; herb- 

 age sparsely white-villous; leaflets broadly ob- 

 cordate or oblanceolate, serrate-setate, 5 to 9 

 lines long; stipules broadly ovate or ovate- 

 lanceolate, entire or toothed ; heads 3 to 5 lines 

 high ; involucre deeply campanulate, becoming 

 flattened at anthesis, 3 to 5 lines wide, 5 to 

 15-lobed, the lobes prominent, green, 3 to 7- 

 toothed; flowers small (2 to 2i/^ lines long); 

 calyx-teeth short, abruptly subulate, scarious and ciliate-margined; corolla white 

 or turning light pink; pods 1-seeded. 



Hillsides and valleys, 20 to 1200 feet : Coast Ranges from San Luis Obispo Co. 

 to Del Norte Co. ; Sacramento Valley. North to British Columbia. South America. 

 Apr.-June. 



Loes. — Coast Eanges: San Luis Obispo, Summers 180; Carmel, Newlon 106; Berkeley, 

 Jepson 10,330a; Mt. Diablo, Jepson 13,661; Sherwood Valley, Mendocino Co., Jepson 1836; 

 Buck Mt., HumlDoldt Co., Tracy 2781; Eequa, Del Norte Co., Bavy. Sacramento Valley: Vaca- 

 ville, Jepson 13,662; Elk Grove, Sacramento Co., Brew; Olinda, Shasta Co., BlanTcinship. 



Var. pilosum Eastw. Smaller ; more or less woolly-pubescent. — San Nicolas Isl. 



Eefs. — Trifolium microdon H. & A. Bot. Misc. 3:180 (1833), type loc. Valparaiso, Chile, 

 Cuming 747; Jepson, Fl. W. Mid. Cal. 308 (1901), ed. 2, 225 (1911), Man. 541, fig. 529 (1925) ; 

 McDer. N. Am. Sp. Trifolium 111, pis. 40, 41 (1910). Var. pilosum Eastw. Proc. Cal. Acad. ser. 

 3, 1:100 (1898), type loc. San Nicolas Isl., Traslc; McDer. I.e. 113; Jepson, Man. I.e. 



15. T. microcephalum Pursh. Maiden Clover. Stems slender, sometimes 

 stoutish, ascending, % to 2 feet high ; herbage soft-pubescent to nearly glabrous ; 

 leaflets obcordate to oblanceolate, retuse, serrate, 3 to 6 lines long; stipules ovate, 

 acuminate; involucre 7 to 10-lobed, the lobes lanceolate, entire with scarious web- 

 like margins; heads small, compact, 3 to 5 lines high; flowers small (2 to 3 lines 

 long) ; calyx shorter to slightly longer than corolla, the teeth entire, pungent, the 

 margin below with a broad scarious border; corolla light pink or white; pods 1 or 

 2-seeded. 



Fig. 197. 

 habit, X 1/2 : 

 open, X 3. 



Trifolium grayi Loja. a, 

 b, fl., X 2 ; c, calyx spread 



