212>. 148. COMPdSltAE. 



103. Ray flowers yellow, shortly strap-shaped. 58 COTULA. 

 Ray flowers white, long strap-shaped. 57 MATRICARIA. 



104. Flowers 4 merous. 105. 

 Flowers 5 merous. 107, 



105. Involucre bracts in several rows, the outer shorter. Inner 



fruits 4 angled. Heads small. 



59 SCHISTOSTEPHIUM. 

 Involucre in 1 — 3 rows, nearly equal. 106. 



106. Pappus ring or crown-shaped. 57 MATRICARIA. 

 Pappus wanting. 58 COTULA. 



107. Heads in leafy racemes, spikes or elongated panicles. 



62 ARTEMESIA. 

 Heads solitary or in corj^mbs. 108. 



108. Involucre in 1 — 3 rows. Bracts nearly equal. Herbs. 



57 MATRICARIA. 

 Involucre in several rows, outer bracts shorter. Stem woody. 



109. 



109. Leaves opposite. Fruits with 10 — 15 ribs. 



60 GYMNOPENTZIA. 

 Leaves alternale. Fruits with 5 ribs. 61 PENTZIA. 



110. Receptacle with scales between the flowers. 111. 

 Receptacle glabrous, rarely hairy, without scales. I22. 



111. Pappus of 5 — 6 large, usually spirally rolled scales, and often 



5—6 bristles inside- 76 URSINIA. 



Pappus wanting or crown-shaped or of small scales, or if of 



large scales, then numbers either 1 — 2 or 8 — 16. II2. 



112. Pappus of feathery bristles. 51 TRIDAX. 



Pappus of simple bristles or scales or wanting. 113. 



113. Pappus at least on inner fruits of 8 — 16 large scales. 



53 GALINSOGA. 



Pappus of 1 — 2 large scales, or of small scales or bristles, or 



wanting. 114. 



I-I4. Marginal flowers persistent in fruit. 41 ZINNIA. 



Marginal flowers not persistent. 115. 



115. Inner fruits compressed from front to back. 116. 



Inner fruits not or laterally compressed. 117. 



116. Ray flowers large white or red. Fruits beaked. 49 COSMOS. 

 Ray flowers if present small. Fruit with prongs. 



48 BIDENS. 



117. Inner fruits much compressed laterally. 



47 SPILANTHES. 

 Inner fruits slightly or not compressed. 118. 



118. Inner involucral bracts embracing outer fruits. 



42 SIEGESBECKIA. 

 Inner involucral bracts not embracing outer fruits. 119. 



