GAYOPHYTUM AND BOISDUVALIA. llg 



Sir William Hooker (London Journ. Bot. 1847, vi. 

 224), distinguishes two forms of this species, a. strictipes, 



and /?. deflexum, respectively with erect and refracted 



capsules (the characters, however, transposed in his descrip- 

 tions, as has been noted by Dr. Gray in Proc. Phila. Acad. 

 1863, 61). Both forms are about equally abundant and of 

 similar distribution. Corresponding forms occur in other 

 species, so that it has hardly seemed desirable to maintain 

 the varieties here unless similar varieties are to be admitted 

 for the others. 



G. caesium Torr. & Gray, Fl. i. 1840, 514. — G. 

 racemosum Torrey & Gr. 1. c; G. Nuttalii Torr. & Gr. 

 1. c. — A span to rarely a foot high, subsimple or diffusely 

 paniculate and fertile from the base, glabrous or with 

 spreading soft pubescence; leaves uniformly distributed 

 along the branches, the upper mostly small and erect; 

 flowers very small, the petals mostly under 1 mm. long; 

 stamens in two sets, the anthers of the shorter ones 

 smaller; stigma globose, large for the genus, .6 to .8 mm, 

 in diameter; capsules .5 mm. wide, narrowly linear, little 

 flattened, nearly sessile, often finely torulose, erect; seeds 

 numerous, nearly erect, smooth, about . 36 X. 93 mm. (vary- 

 ing from .25 to .50X.76 to 1.17 mm). — Oregon to the Yel- 

 lowstone, Colorado, and California. 



Specimens examined from Oregon (Nuttall's type of 

 Oenothera cresia; Douglas; Union Co., Cusick, 1877), 

 Idaho (Beaver Canon, Watson, 1880, 148), Yellowstone 

 region (Hayden, 1859-60 ?, with diffusum). Rocky Mount- 

 ains (Hall & Harbour, 1862, 171, and 172 in part in 

 some sets; Nuttall, types of O. micrantha and O. ra- 

 cemosa in hbs. Gray and Torrey), Colorado (Empire, 

 Patterson, 1892, 207; Steamboat Springs, Miss East- 

 wood, July 1891; Breckenridge, Brandegee, 1871, 169), 

 Utah (Alta, Jones, 1879, 1249; Palmer 1877, 157 in 

 part), Nevada, (Aurum, Jones, June 12, 1893 — a 

 canescent f orm ; Carson Valley, Stretch, 1865, 179; Clover 

 Mts., Watson, 1868, 403; E. Humboldt Mts., Watson, 



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