322 LOASACE^. 



Calyx-tube adnate to the 1-celled ovary, its. limb 5-lobed. Petals 

 commonly 5. Stamens usually very numerous, inserted with the 

 petals on the throat of the calyx. Placentae 2 or 3, parietal. Pruit 

 a capsule, crowned with the calyx-lobes. 



1. MENTZELIA L. 



Erect annuals. Leaves in age brittle, adhering very tightly to 

 clothing by means of barbed hairs. Plowers terminal, solitary or 

 cymose, small or showy. Styles 3, more or less united into one. 

 Capsule dehiscent at the summit, few to many-seeded. Seeds flat; 

 endosperm scanty. (Named for C. Mentzel, a German botanist of 

 the 12th ceiitury. ) 



Annuals; capsule linear or clavate ; petals 5, 

 Mostly 2 lines long or less. 

 Floral leaves broad, almost concealing the flowers; seeds raucli longer 



than broad 1. M. micrantha. 



Floral leaves very much shorter than the flowers; seeds cubical 



2. M. dispersa. 

 Mostly 4 lines long or more. 



Capsule linear, hispid; petals pale yellow, 3 or 4 lines long 



3. M. affinis. 

 Capsule linear-clavate to obconic. 



Petals about J^ in. long . 4. if. gracilenta. 



Petals 1 to 1^ m. long, golden-yellow . . . , . 5. M. Lindleyi. 

 Biennial; capsule oblong; petals 10 &. M. Ixvicaulis. 



1. M. micrantha T. & G-. Kough-hispid, at least above; stems 

 simple below, oorymbosely and rather compactly dichotomous above; 

 leaves ovate, acute or acuminate, serrate or sinuate-toothed, 1 to 2 in. 

 long or the uppermost roundish, entire, and 4 to 6 lines long; flowers 

 shorter or scarcely exceeding the broad floral leaves; petals oval or 

 obovate, IJ to 2 lines long, twice longer than the calyx-lobes; 5 of the 

 filaments petal-like with emarginate apex; capsule linear, sharply 

 triangular, 3 lines long; seeds 1 line long, twice as long as broad. 



Coast Range hills from Saratoga, Santa Clara Co., Davy, Sept., 

 1893, to Mt. Diablo. Clear Lake, ace. to Bot. Cal. 



2. M. dispersa Wats. Usually branching, 9 to 13 in. high; 

 stems ostensibly smooth, pubescent under a lens; leaves oblong or 

 ovatish, IJ in. long or less, entire or sometimes toothed; flowers 

 small, approximate near the ends of the branches; calyx-lobes 1 line 

 long, little shorter than the obovate petals; filaments not dilated; 

 capsule linear, 6 or 7 lines long; seeds cubical, minutely mottled, 

 rather acutely angled, as broad as long. 



Montane species: Lower Lake Grade to Kelseyville; Mt. Diablo. 

 Also credited to the Sierra Nevada. 



3. M. affinis Greene. Stoutish, simple and leafy below, widely 

 branching above, 2 or 3 ft. high; leaves lanceolate in outline, deeply 

 and often sharply pinnatifid; flowers 5 or 6 lines broad, numerous but 

 not congested; calyx-lobes subulate, 2 lines long; capsule linear, sub- 

 terete, I to nearly 1 in. long, hispid with short stiff' white hairs; seeds 

 prismatic with grooved angles. 



San Joaquin Valley plains; (?)Aatioch. Insuffioiently distin- 

 guished from the next. 



