86 Contributions from the Gray Herbarium 
the crest often purple, 2.5-3 mm. long. Upper sepal broadly 
ovate, obtuse, 1.5 mm. long, the lower oblong, 1.3 mm. long. 
Wings obliquely elliptic, rounded at apex, shortly cuneate at base, 
2.9 mm. long, 1.6 mm. wide. Keel 3 mm. long; crest of 4 pairs of 
lobes, the posterior cuneate, the 3 anterior linear, entire. Upper 
petals ovate, obtuse, 2.8 mm. long. Capsule elliptic or oblong- 
elliptic, 2.5-2.9 mm. long, 1.3-1.6 mm. wide. Seed appressed- 
pilose, 2.3-2.5 mm. long. Aril (0.8) 1.3-1.5 mm. deep, its oblong 
obtuse lobes appressed. — Divisible into two varieties. 
\ Var. tenuifolia (Pursh), comb. nov. Folia omnia alterna (verti- 
cillis 1-2 basalibus exceptis). — P. Seneca var. y. tenuifolia Pursh, 
Fl. Am. Sept. ii. 750 (1814). P. alba Nutt.! Gen. ii. 87 (1818); 
Wats. Proc. Am. Acad. xxi. 416 (1886); Chod. Monog. ii. 135. t. 
20. f. 13-14 (1893). P. bicolor HBK.! Nov. Gen. v. 394. t. 507 
(1821). P. alba Nutt. var. bicolor (HBK.) Chod. 1. c. 136 (1893). 
P. Torreyi G. Don, Gen. Sys. i. 360 (1831); Greene, Pitt. ii. 307 
(1898). P. Beyrichii T. & G.! Fl. N. Am. i. 130 (1838). P. scoparia 
Benth.! Pl. Hartw. 8 (1839), not HBK. P. alba Nutt. var. brachy- 
stachya Chod.! 1. c. 136 (1893); var. leptostachya! and var. mexicana 
Chod. 1. c. 137. — Sonora: Fronteras, 1390 m., 24 Sept. 1890, 
Hartman 40 (G); Sept. 1851, Thurber 1092 (G). CHIHUAHUA: 
Santa Eulalia Mts., 27 Oct. 1885, Pringle 299 (rypE COLL. of var. 
brachystachya: BG); San Antonio de las Alanzanes, 1848-49, Gregg 
371 (GK). Coanvuma: Sierra Madre, 64 km. south of Saltillo, 
July 1880, Palmer 68 (G). Duranco: near City of Durango, 1896, 
Palmer 129 (BG); Tejamen, Aug. 1906, Palmer 537 (G); Tepe- 
huanes, Mar.—Apr. 1906, Palmer 43 (G). Zacatecas: Coulter 725 
(GK); Guadalcajar, 1883, Dugés (G). AGuas CALIENTES: near 
Picocho, Hartweg 30 (BGK). Guanasuato: Santa Rosa, Hum- 
boldt & Bonpland (fragm. of tyPE of P. bicolor: G). San Luts 
Porost: 1878, Parry & Palmer 39 p. p. (K). Pussia: San Luis 
Tultitlanapa, June 1908, Purpus 3502 (G); Bagre, Minas de San 
Rafael, May 1911, Purpus 5165 p. p. (G). Sierra Madre, Mexico: 
Seemann (G: toward var. suspecta). Mexico without locality: 
Beechey (K). —T. 2. Fria. 61. 
Var. susPpEcTA Wats. Folia usque ad mediam partem caulis ver- 
ticillata. — P. alba Nutt. var. (?) suspecta Wats.! Proc. Am. Acad. 
xxi. 416 (1886). P. alba var. Schaffneri Chod. Monog. ii. 137 (1893). 
—Cuimuanva: 240 km. north of Batopilas, 1375 m., Nov. 1885, 
