180 Class XIX. Order III. 



D. Flowers radiate. 



231. CHRYSANTHEMUM. Receptacle naked ; 

 down none ; calyx hemispherical, imbricate, with 

 the scales dilated, and membranous at the margin. 



%32. ERIGERON. Receptacle naked ; down 

 simple ; florets of the margin very numerous and 

 narrow, linear. 



233. SOLIDAGO. Receptacle naked, pitted ; 

 down simple ; florets of the margin from five to ten, 

 remote ; calyx imbricate, closed. 



234. SENECIO. Receptacle naked ; down sim- 

 ple ; calyx invested with scales, many leaved, 

 equal ; the scales dead at their tips. 



235. ASTER. Receptacle naked; down sim- 

 ple ; calyx imbricate, with the lower scales spread- 

 ing ; florets of the margin commonly more than ten. 



236. ANTHEMIS, Receptacle chaffy ; seeds 

 crowned with a slight border ; calyx hemispheric- 

 al ; florets of the ray more than five, oblong. 



237- ACHILLEA. Receptacle chaffy ; down 

 none ; calyx ovate, imbricate, unequal ; florets of 

 the ray from five to ten, inversely heart-shaped or 

 roundish. 



Order III. FRUSTRJHVEJ. Florets of the centre 



with stamens and pistils, fertile ; those of the ray udth pistils 

 only, barren. 



238. HELIANTHUS. Receptacle chaffy ; seeds 

 crowned with two lanceolate, chaffy scales ; calyx 

 imbricate, somewhat squarrous. 



239. COREOPSIS. Receptacle chaffy: seeds 



