LILY-OF-T}IE-\'ALLEY FAMILY 



451 



2. Trillium rivale S. Wats. 

 Brook Trillium. Fig. 1105. 



Trillium rizalc S. Wats. Proc. Am. Acad. 20: 378. 1885. 



Stem slender, 10-20 cm. high. Leaves ovate- 

 lanceolate, rounded or subcordate at base, acute or 

 acuminate. 25-45 mm. long ; petioles 5-25 mm. long ; 

 pedicels slender, erect or at length declinate, a little 

 shorter or longer than the leaves; petals 15-20 mm. 

 long, white or marked with purple, rhombic-ovate, 

 acute; filaments about equalling the anthers; berry 

 globose, 10-15 mm. broad, scarcely angled. 



Stream banks. Humid Transition Zone; Coast Ranges and 

 the Siskiyou Mountains of southern Oregon and adjacent Cali- 

 fornia. Type locality: Big Flat, 30 miles east of Crescent 

 City, California. 



3. Trillium chloropetalum (Torr.) Howell. 

 Giant Wake-robin or Trillium. Fig. 1106. 



Trillium 



1841. 

 Trillium 



1857. 

 Trillium 



1857. 

 Trillium 



273. 

 Trillium 

 Trilliu m 



1903. 

 Trilliu m 



4: 50. 

 Trillium 



4: 51. 



sessile gigantcum Hook. & Arn. Bot. Beechey, 402. 



sessile chloropetalum Torr. Pacif. R. Rep. 4: 151. 



sessile angustipetalum Torr. Pacif. R. Rep. 4: 151. 



sessile calif ornicum S. Wats. Proc. Am. Acad. 14: 



1879. 



chloropetalum Howell, Fl. N. W. Am. 1: 661. 1902. 



gigantcum Heller, Bull. S. Calif. Acad. Sci. 2: 67. 



giganteum chloropetalum Gates, Ann. Mo. Bot. Hard. 



1917. 

 giganteum angustipetalum Gates, Ann. Mo. Bot. Gard. 



1917. 



Stems stout, one or more arising from the very 

 stout rootstock, 3-5 dm. high. Leaves round-ovate, 

 8-15 ctti. long, and nearly or quite as wide, usually 

 conspicuously mottled with dark splotches, obtuse to 

 somewhat accuminate at apex, rounded to the sessile 

 base; flowers sessile; sepals narrowly to rather broadly oblong-lanceolate, 3-5 cm. long, petals 

 obovate to linear-lanceolate. 4-9 cm. long. 8-35 mm. wide, deep maroon varying to greenish 

 yellow or white; anthers 15-25 mm. long; berry strongly winged, green or red. 



Wooded slopes. Transition Zone; western Washington, where it has been collected at Roy, southward to 

 San Luis Obispo and Mariposa Counties, California. Type locality : "Redwoods," probably in the vicinity 

 of Point Reyes, California, where the greenish yellow form is prevalent. From Mendocino and Napa Coun- 

 ties, California, northward, the prevailing form is white or yellowish white, often with a purple base. In the 

 San Francisco region south to Monterey the maroon form is prevalent; this was originally described as 

 sessile gigantcum. The narrow-petaled form was described as sessile angustipetalum Torr., from specimens 

 collected in the Mariposa Big Tree Grove. It is the prevailing type in the Sierra Nevada, but also occurs 

 in the San Francisco Bay region. 



4. Trillium petiolatum Pursh. 

 Petioled Wake-robin or Trillium. Fig. 1107. 



Trillium petiolatum Pursh, Fl. Am. Sept. 1: 244. 1914. 



Stems from a short stout rootstock, 5-15 cm. 

 long, but mainly subterranean, usually only 2-3 

 cm. above the ground. Leaves round-ovate 6-15 

 cm. long, 5-10 cm. wide, rounded or obtuse at 

 apex, rounded at base to a stout petiole, 5-12 cm. 

 long; flowers sessile in the axils of the petioles; 

 sepals oblong-linear, 15-35 mm. long. 5-7 mm. 

 wide, erect ; petals narrowly oblanceolate, 25-45 

 mm. long, 5-10 mm. wide, maroon color ; anthers 

 10-15 mm. long, exceeding the stigmas, on very 

 short filaments ; stigmas slender, 10 mm. long, but 

 little spreading. 



Moist rich soil usually in copses. Arid Transition Zone; 

 eastern Washington and Idaho south to eastern Oregon. 

 Type locality: Lolo River, Idaho. 



