ASTERACEAE 



33 



1. Flowers in an oblong prickly head 



_\ l lowers in .1 il.it head, withool prickles 



Dip 



I tfpsacus Teasel 



Kir. dipsakos, 



i ilong ; flowers bluish 



1). julU'inum 



Scabiosa — Sw eel Scabii ms 



il.at. scabies. Itch, from Its repute In skin dla 



1. Flowers purple, red or white 

 J. I low i i ^ lighl bine 



S. atropurpurea 



S. I t'li. .; 



Asteraceae — Aster Family 



Herbs with flowers in dense involucrate heads; sepals (pappus) in form of bristles, scales, I 

 etc., i>r wanting, petals 5, stamens 5 or 0, united by their anthers; ovary 1 celled, 1-ovuled, style 1, 

 2-cleft, stigmas 1; flower syncarpous, sympetalous, regular or irregular, epigynous. The Mowers of the 

 hiid may be all tnbe-shaped, or the outer row or so may he ribbon-shaped, or all may he ribbon- 

 shaped. The receptacle is flat or more or less conical, naked (i. e., bearing only the flowers 

 bearing scales among the flowers. The head is surrounded by 1 or more rows of involucral bracts. 



Key to the Genera 

 1. Flowers tube-shaped, no ray or ribbon-like Mowers present 



Tubular heads of Lacinlavla long section, and tube-shaped dower. 



a. Flowers bright-Colored; heads conspicuous 

 (1) Leaves or involucre spiny 



(a) Leaves spiny 



\. Pappus of plumy hri-tlr S 



(x) Involucral scales thick and fleshy; cultivated Cynara 



(y) Involucral scales not thick and Meshy; native Carduui 



y. Pappus none Carthamus 



(b) Involucre spiny with hooked spines Arctium 

 Leaf and involucre without spines 



(a) Heads in long spikes Laciniaria 



