228 CARDUACEAE 



Herbs, if at all slirubby only at the base; bracts more or less scarious. 



Receptacle chaffy; style or style-branches of the hermaplirodite sterile flowers not 

 truncate. 

 Pistillate flowers all sixbtended by paleae and without pappus 



Paleae in fruit enclosing the achenes and falling off with them, tipped with a 



hyaline appendage. 



Heads ovoid; paleae subtending the pistUlate flowers boat-shaped, with 



erect conspicuous hyaline tips, those of the 4-5 hermaphrodite 



flowers barely concave or plane. 



Paleae subtending the central flowers hyaUne and deciduous: bracts 



of the involucres in several series. 50. Styl/mlixe. 



Paleae subtending the central flowers coriaceous-herbaceous, ending in 

 a hooked spine, persistent; bracts of the involucres none beside the 

 paleaceous ones enclosing the marginal flowers. 



51. Ancistroc.\rphus. 

 Heads globose; paleae subtending the pistillate flowers cucullate-saccate 



and utricular, the ape.x introrse and the ovate appendage inflexed or 

 porrect; paleae and pappus of the hermaplu"odite flowers lacking. 



52. PSIIX)C.\RPUS. 



Paleae in friiit open and merely subtending the achenes, without a hyaline 

 appendage. " 53. Di.\peri.\. 



Pistillate flowers of two kinds, the outer with, the inner without pappus, the latter 

 and the central fertile hermaphi-odite flowers not subtended by individual 

 paleae, but the cluster surrounded by a ring of open scarious paleae, the 

 outer subtended by boat-shaped ones. 54. Oglif.\. 



Receptacle not chaffy; style or style-branches of the hermaphrodite flowers mostly 

 truncate. 

 Plants dioecious, or the pistillate heads with a few hermaphrodite flowers in the 

 center. 

 Pappu.s-bristles of the pistillate flowers falling off in a ring; central hermaph- 

 rodite flowers none. 5.5. Axten'x.'V.ria. 

 Pappus-bristles of the pistillate flowers falling off separately; central hermaph- 

 rodite flowers present m the pistUlate heads. 56. Anaph.\LIS. 

 Plants not dioecious; flowers fertile throughout the heads, hermaphrodite in the 

 middle, surrounded by pistillate ones. 57. Gn.\ph.\lium. 



Tribe 5. ADENOCAULEAE. 

 Leaves cordate, white-woolly beneath. 5S. Adexocaulox. 



Tribe 6. HELIAXTHEAE. 

 A. Bracts (at least the outer series) not enclosing the achenes of the rays; plants not 

 glandular- viscid. 



I. Disk-flowers hermaphrodite but sterile. 



Marginal pistillate flowers, with conspicuous rays. 



Achenes not flattened; ligules in ours wliite; involucres of very dissimilar sets 



of bracts. 59. Mel-AMPOdiu.m. 



Achenes flattened; ligules in ours yellow. 



Ray-flowers in 2-.3 series; achenes falling awav free. 



60. SILPHIUM. 



Ray-flowers in 1 series; achenes adnate to 2 or 3 paleae and falling away 

 with them. 61. Exgelmaxxia. 



Marginal pistillate floweis reduced to a trimcate or obliquely-cleft tube; the 

 Ugules, if any, reduced to 2 or 3 small teeth. 

 Acatflescent cespitose perennials; pappus of a pair of lanceolate membranous 



scales. 62. Bolophyta. 



Caulescent annuals; pappus none. 63. Parthexice. 



II. Disk-flowers fertile. 



a. Ray-flowers fertile; the ligules with very short tube, persistent on the achenes 



and becoming papery in texture. 

 Achenes of the disk compressed ; leaves entire. 64. Crassix.\. 



Achenes obtusely 4-angled. 



Leaves toothed; paleae pointless, partly enclosing the achenes. 



65. Heuopsis. 

 Leaves entire : paleae linear-lanceolate, not enclosing the achenes. (§ Kalliac- 

 tis, i. e., B. Carcyana, of i 71. Balsamorrhiza. 



b. Ray-corollas deciduous from the achenes or wanting. 



1. Pappus a crown or none, or of a few squamellae on the angles of the achenes, 

 and rarely minute ones between. 

 a. Achenes of tlie disk-flowers not obcompres.sed (except in Ralibida and 

 Ximenesia)' paleae usually more or less concave and clasping. 

 Receptacle conic, subulate or cohunnar. 

 Achenes 4-angled. 



Ray-flowers purplish or rarely whitish: disk-corollas almost 



without a tube: pappus coroniform. 66. Br.\i n'f;ri.v 

 Ray-flowers yellow or none; di.sk-corollas with a short but mani- 

 fest tube. 

 Achenes quadrangular-compressed: apex of the achenes 

 covered by the base of the corolla-tube. 



67. GY'MXOLOMIA 

 Achenes nearly equally 4-angled; apex not covered by thp 

 base of the corolla. 6S. Rudbeckia, 



Achenes 5-angled ; ray-flowers white. 70. Galixsoga. 



