THISTLE FAMILY 899 



YI. Dectjmbextes. 



Leaves l-nerv^ed, linear-oblanceolate; the lo-n-er usually obtaisish. 26. E. Engelmannii. 

 Leaves 3-nerved, at least at the base, equally long-acuminate at both ends. 



Pubescence of the leaves loose, hirsute and somewhat glandular-puberulent. 



40. E. decumbens. 



Pubescence of the leaves appressed-strigose. 41. E. microlonchus. 



YII. El.\tiore.s. 

 Bracts verj' densely villous, squarrose; leaves entire. 42. E. elatior. 



Bracts sparingly -v-illous; leaves usually dentate. 



Ligules white; bracts scarcely squarrose; stem sparingly pubescent. 



4.3. E. Coulteri. 

 Ligules blue or purple; bracts squarrose; stem densely pubescent above. 



44. E. peregrinus. 



VIII. Saistjgixosi. 

 Rootstock thick; leaves thickish, acute; bracts narrowly Unear-lanceolate, with strongly 

 spreading tips. 

 Peduncles mostly solitary, finely strigose; stem, single from the rootstock. 



45. E. salsuginosus. 

 Peduncles iisually more than one, scabrous; stems several from a caudex. 



49. E. eucephaloides. 

 Rootstock slender; leaves thin, with long mucronate tips; bracts narrowly linear-subu- 

 late, only shghtly spreading. 46. E. Howellii. 



IX. Macranthi. 



Basal leaf-blades broadly obovate-spatulate, often denticulate; stem-leaves distant, 

 shorter than the intemodes, not ciUate on the margins; braxits glandular-puberulent, 

 seldom with a few hairs. 47. E. superbus. 



Basal leaf-blades oblanceolate, entire; stem-leaves usually longer than the intemodes, 

 usually ciliate on the margins. 

 Bracts linear-subulate, glandular-puberulent, not at all hirsute; leaves glabrous. 

 Leaves hnear-lanceolate, minutely cUiolate. 



Leaves dark green; bracts not with loose tips. 48. E. salicinus 



Leaves light green; bract with spreading tips. 49. E. eucephaloides. 



Leaves not dark green, duU, strongly hirsute-ciUate. 50. E. macranthus. 



Bracts linear, more or less hirsute. 



Stem and leaves glabrous or nearly so; the latter cUiate only on the margin and 

 the veins below; bracts glandular-puberulent and with scattered hairs. 



51. E. speciosus. 

 St€m and leaves hairy; bracts hirsute or both hirsute and glandular. 



Leaves hirsute. 



Pubescence scant, that of the stem long; leaves linear-lanceolate. 



52. E. conspicuus. 

 Pubescence of the leaves and the involucres dense, that of the stem short. 



Plant tall, green; upper stem-leaves ovate or ovate-lanceolate, dis- 

 tinctly triple-nerved. 52. E. subtrinertis. 

 Plant low, canescent; upper stem-leaves lanceolate, scarcely triple- 

 nerved. 54. E. incanescens. 

 Leaves glandular-puberulent. 55. E. Vreelandii. 



X. GL-Vbelli. 



Involucre hirsute or strigose, not at aU glandular. 



Leaves glabrous, except the ciliate margins. 56. E. glabellas. 



Leaves more or less pubescent. 



Pubescence loose and spreading. 57. E. fruticetorum. 



Pubescence appressed. 58. E. Earlei. 



Involucres morp or less glandular, sometimes also hirsute. 

 Leaves glabrous, exoopt the ciliate margins. 



lightly glandular 



or pink. 

 ■ u A - idular; stem low, usually 



ln.^^^rtfAy^it aU hh^te; stem 3 dm. hlgh-or moF^g-'?--^^^^ 

 more than one head. ^. 7^' P rnuiiPri 



Bracts lance-subulate; Ugules white. if v %mihii' 



Stem scarcely hairy, decidedly glandular above. 61. E. bmitnu. 



Leaves and stem more or less pubescent. . v,^,-,™ 



Involucres about 18 mm. broad; plant conspicuously long-hau^ formosissimus. 



Involucres about 15 mm. broad; plant less conspicuously ^fir^j'^^^^rff^^^^^^'"- 



XI. Philadelphici. 

 Basal leaves crenate or dentate, with broad rounded or ovate ^eeth; upper^l^eaves l^anceo- 

 BaslY?^\^^^de^^Ite"STha^r^triangular, saUent teeth; upper |t|m4e|ves tr^ngular- 

 lanceolate, actuninate; rays rose-colored or purple. bo. E. purpureub. 



XII. ASPERI. 



Pubescence short, usuaUy not dense. TM,=iniiato ha<!P5 



Pubescence appressed or rarely spreadmg; hairs not with pustulate oasea. 



