28 POLYGONACE^E. Eriogonum. 



36. E. fasciculatum, Benth. 1. c. Shrubby, more or less tomentose and often 

 somewhat villous : leaves narrowly oblanceolate, acute, nearly sessile, usually 

 strongly revolute, tomentose beneath, often glabrate above, 3 to 9 lines long, much 

 fascicled : peduncles short or elongated, bearing a short cyinosely divided umbel 

 often much contracted or capitate : bracts more or less conspicuous : involucres 

 about 2 lines long, pubescent or glabrate : flowers rose-colored or whitish, glabrous 

 or often more or less villous. Torr. & Gray, 1. c. E. rosmarinifolium, Nutt. PI. 

 Gambel. 164. E. polifolium, Benth. 1. c. E. ericcefolium, Torr. & Gray, 1. c. 170. 



From the coast of Southern California (Santa Barbara and southward) east to Arizona and 

 Southern Utah. Very variable in pubescence, etc., but the forms scarcely merit the rank of 

 varieties. E. polifolium is a common hoary form with less revolute leaves and elongated pedun- 

 cles. E. ericcefolium was founded upon very reduced specimens with short branches and small 

 almost sessile heads ; it occurs in Arizona and S. Utah. 



*- ) Perennials or annuals, leafy below : leaves not fascicled : bracts small., 

 the lower very rarely foliaceous : involucres mostly solitary, in an open 

 and repeatedly di- or trichotomous corymb-like cyme : perianth glabrous. 

 ( CORYMBOSA, Benth.) 



H- Perennial, woody and much branched, leafy below. 



37. E. microthecum, ISutt. Low and diffuse, rather slender, 3 to 1 2 inches 

 high, more or less white-tomentose : leaves oblanceolate to linear, usually narrow, 

 \ to \\ inches long, acute, more or less strongly revolute, white-tomentose beneath, 

 becoming glabrate above, shortly petioled : peduncles short, bearing a short umbel 

 of 3 to 5 more or less (once to thrice or more) subdivided rays : involucres usually 

 small, to 1 \ lines long, attenuate at base and especially the alar ones often pedun- 

 culate : flowers a half to a line long, from nearly white to deep rose-color or rarely 

 yellow. Torr. & Gray, 1. c. 1 70. 



A very variable species, frequent in the mountains of the Great Basin and in the Eocky Moun- 

 tains from Oregon and the eastern side of the Sierra Nevada to Nebraska and New Mexico. 

 Reduced alpine forms are found at 8,000 to 10,000 feet altitude, Mono and Sonora Passes, and 

 Silver Mountain, Bolander, Brewer. The var. ejfusum, Torr. & Gray (E. effusum, Nutt. ), with 

 more diffuse and repeatedly branched inflorescence is common in the Rocky Mountains but not 

 westward. 



38. E. corymbosum, Benth. Stouter and more rigid, usually densely tomen- 

 tose : leaves usually longer and broader, ovate- to oblong- oblanceolate, and less 

 revolute : umbel stiff, broadly cymose : involucres mostly sessile, a line or two 

 long : flowers 1 or 2 lines long. DC. Prodr. xiv. 1 7 ; Torr. & Gray, 1. c. E. micro- 

 thecum, var. (?) Fendlerianum, Benth. 1. c. ; Torr. & Gray, 1. c. 



In diy valleys and on the foothills from the base of the Sierra Nevada eastward. Forms occur 

 apparently connecting this species with the last. 



H- -H- Annual : leaves mostly rosulate at the base, a whorl rarely subtending the 



nodes. 



39. E. truncatuxn, Torr. & Gray. A foot high, floccose-woolly throughout, 

 slender: leaves oblanceolate, an inch long, attenuate to a slender petiole, less 

 tomentose above, the margin undulate : peduncle short, bearing a leafy-bracted 

 umbel of 4 to 6 elongated rays, which are loosely once or twice di- or trichotomous : 

 bracts very small : involucres few, tomentose, oblong-turbiuate, 2 lines long : flow- 

 ers light rose-color, a line long. Proc. Am. Acad. viii. 173. 



On dry hillsides at Marsh's Ranch, east of Mount Diablo, Brewer. In flower, May 29. 



40. E. Mohavense, Watson. A foot high or less, very slender, glabrous above 

 the base, diffusely branched : leaves rounded or ovate, tomentose, half an inch long 

 or less, abruptly narrowed to the slender petiole, all radical : peduncle short, bearing 

 a naked umbel of 3 or more rays, repeatedly dichotomous with very slender joints : 



