652 COMPOSITAE 
faintly 3-nerved. Heads with about 4 white rays and few tubular disk 
flowers, the heads in a spreading flat cluster. Dry soil, northern part of 
our range. June-Sept. 
2. §S. asteroides, (L.) BSP. (Fig. 3, pl. 178.) Toornep Wuitr- 
TOPPED ASTER. Stem 1 to 2 ft. high, angled. Basal and lower leaves in- 
versely egg-shaped, toothed at margins, narrowed to long leaf-stalks, the 
upper leaves lance-shaped, scarcely toothed. Ray flowers about 4, white. 
Dry woods, throughout our range. July-Sept. 
14. ASTER, L. 
Herbs, with alternate leaves and with flower heads in broad, flat or 
more or less elongated clusters, the heads including both tubular (disk) 
and ray flowers, the latter in a single row. Involucre scales more or less 
overlapping, usually with green tips. Receptacle flat or convex, with cir- 
cular depressions (alveolate). Disk flowers tubular, with stamens and 
pistils, usually yellow. Ray flowers with pistils only, white, purple, blue, 
never yellow. Fruit mostly flattened with an aigrette of hair-like bristles, 
rarely double. 
A genus of very numerous species, more abundant in this country than 
in Europe. Professor Edward 8. Burgess, who has for many years made 
special study of the asters of our region, has added many new species 
and many sub-species. It has not been thought necessary to include the 
latter nor even all of the former in this work. 
1. Inflorescence not Unilateral 
Lower leaves broad, egg-shaped, heart-shaped at base, on slender leaf-stalks 
a. None of the leaf-stalks clasping the stem 
Ray Flowers White or nearly White 
Leaves thin, smooth or nearly so. 
Flower stem not as long as the head . - » « « A. carmesinus 
Flower stem as long as or longer than the head. 
Leaves of the branches egg-shaped . . . . . . . A. divaricatus 
Leaves of the branches lance-shaped . . . . . . A. tenebrosus 
Leaves thick and rough. 
Inflorescence round or dome topped. 
Upper stem leaves egg-shaped . . . . . . . . A. glomeratus 
Upper stem leaves lance-sshaped . . . . . . . . A. curvescens 
Inflorescence nearly flat, spreading . . . . . . . . . A. Schreberi 
Inflorescence irregularly diffuse . . . . . . . . . .« A, Claytoni 
Ray Flowers Violet 
Middle stem leaves not sharply and conspicuously toothed. 
Upper and middle leaves nearly round . . . . . . . . A. roscidus 
Upper and middle leaves egg-shaped . - + « A, danthinus 
Middle stem leaves very sharply and conspicuously toothed. 
Inflorescence nearly flat; broader leaves kidney-shaped . . . A. violaris 
Broader leaves egg-shaped ree SS eg fe ee oe 
Inflorescence guite irregular . «© « «© »s «6 «© «= « «o © ) si s4,mOOMER 
Ray Flowers Blue 
Leaf-stalks without winged margins, or with very narrow margins. 
Scales of the conical involucre lying close and flat, with green tips 
Steet. Ns | iO ne Rly rn PR enya SC Rie ee A. cordifolius 
Scales of the oblong involucre spreading, not lying flat . . A. sagittifolius 
Leaf-stalks conspicuously margined. 
Inflorescence conical . . . . »« »« « «© »« » « »« « A, DLowrieanns 
Inflorescence pyramidal . . . . . « « «© « » « « && 2snasevanes 
