DICOTYLEDONES 



457 



which either all the flowers are tubular and alike (Cirsium, Cynara), or the 

 marginal or ray flowers are provided with showy flattened corollas, while 

 the centre of . the inflorescence is occupied by the tubular "disk-florets" 

 (Fig. 448, D). 



The Compositae are cosmopolitan, and are admirably adapted to survive in the 

 struggle for existence. Innumerable devices for distributing the seeds have been 

 developed, and render some of the Compositae the most troublesome of weeds. 

 The winged fruits of Dandelions and Thistles, and the burs of Burdock and 

 Clotbur, may be cited as examples of these devices for distributing the fruits. 



FIG. 448., A-C, Taraxacum offlcinale ; c, strap-shaped corolla ; o, ovary ; d, receptacle 

 with two fruits attached. D, E, Anthemis cotula ; r, ray-florets. E, single disk 

 floret ; an, stamens. 



Classification of Sympetalae 

 SERIES III. METACHLAMYDE^E 

 Order I. Ericales 



Petals free f fam 



' ' free or united I 



" united, root parasites 



" united, hypogynous or epigynous. 



Haplosternonous 



Anisocarpous 



1. Clethraceae 



2. Pirolaceae 



3. Lennoacese 



4. Ericaceae 



6. Epacridaceae 



6. Diapensiacese 



