BUCKWHEAT FAMILY 



215 



Leaves densely villous on both sides. 85. E. bicolor. 



Pedimcles clavate-thickened upwards. 86. E. clatellatum. 



Branches of the inflorescence strongly angled and deeply grooved. 



87. E. sulcatum. 



One species. 



XIV. Axxu.\. 



XV. R.\CEMOS.i. 



88. E. annuum. 



Leaves crowded on the short branches of the caude.x; blades abruptlv narrowed at the 

 base or subcordate. 89. E'. racemosum. 



Leaves scattered on the fruticose branches; blades tapering at the base. 



Leaf-blades elliptic or oblanceolate. 90. E Wrightii 



Leaf-blades linear. 91. £. leptocladon. 



XVI. VlHG.\T.\. 



Stem neither divaricately branched, nor denselv floccose. 



Involucres cylindric; perianth-segments oblong or oval; plant with few branches 

 Involucres about 3 mm. long. 92. E. rimineum 



Involucres about 2 mm. long. 93. E. Baileyi. 



Involucres campanulat*, 1-1. .5 mm. long; perianth-segments cuneat«, flabeUate, or 

 fiddle-shaped; plants with numeroiis branches. 

 Branches not incurved in age; leaf-blades ovate or oblong. 

 _, , . 94. E. densum. 



Branches mcurved m age; leaf-blades orbicular or subreniform. 

 „.,..,, , 95. E. nidularium. 



stem davancately branched, densely floccose. 96. E. Plumalella. 



97. E. tenellum. 



XVII. Pedu.vcul.\t.\.. 



Perennials with a woody caudex. 

 Annuals. 



Perianth glabrous or in E. Thomasii and E. nutans somewhat pubescent; segments 

 mostly obtuse or rounded at the apex. 

 Peduncles not glandular. 



Scape and its branches glabrous. 



Pedimcled reflexed or at least divaricate; leaves tomentose on both sides, 

 less so above. 

 Involucres 1.5-2 mm. long; perianth 1.5-2 mm. long. 

 • Peduncles shorter than the involucres ; outer perianth-lobes ovate or 

 subreniform. 

 Perianth pale yellow; outer segments subreniform. 



98. E. Hookeri. 

 Perianth white; outer segments ovate. 99. E. deflexum. 

 Pedtmcles longer than the involucres; out«r perianth-segments 

 obovat« or panduriform; perianth white or pinkish. 



100. E. cernuum. 

 Involucres 0.5 mm. long; perianth 1-1.5 mm. long, veUowish with red- 

 dish veins. 101. E. Wetherillii. 



Peduncles erect or ascending. 



Leaves more or less tomentose beneath. 

 Involucres 1.5-2 mm. long. 



Perianth yellow; segments similar. 102. E. pusillum. 



Perianth white or rose-colored; segments unlik e 



Involucres campanulate; outer perianth-segments flabellate. 



103. E. rotundifolium. 

 Involucres tiu-binate; outer perianth-segments not flabellate. 

 Outer perianth-segments oblong-ovate, the inner ones 



entire. 104. E. insiqne. 



Outer perianth-segments subreniform. the inner ones 3- 

 toothed, much smaller. 105. E. turbinatum. 



Involucres scarcely 1 mm. long; perianth yellowish or white, usually 

 somewhat hispidulous at the base. 106. E. Thomasii. 



Leaves green, glabrate or sparingly pilose. 107. E. Gordonii. 

 Scape more or less pubescent, at least at the nodes. 

 Leaves white-lanate beneath. 

 Leaves green on both sides, sparingly pilose. 

 Peduncles glandular; leaves tomentose. 



Outer perianth-segments oval, emarginate or retuse. 



108. 

 109. 



E. subreniforme. 

 E. trinertatum. 



Outer perianth-segments ovate-cordate, the inner 



the inner ones oblong. 



110. E. nutans. 



ones oblong-ovate, acute. 



111. E. Parryi. 



Per^nth pubescent ; segments ovate or lanceolate, acute. 



Peduncles and usually also the scape glandular; leaves green, merelv hirsute be- 



neath. 112. E. glandulosum. 



Peduncles and scape not glandular. 



Leaves floccose or tomentose beneath. 113. E. Ordii. 



Leaves green, merely pilose or hirsute. 



Accessory branches at the lower forks of the inflorescence many and nearly 

 as strong eis the primary ones; all divaricate. 

 Scape slightly if at all inflated. 114. E. trichopodum. 



