I.] 



COMPOSITE. 



175 



ray of the Daisy in form ; they are all ligulate and 

 yellow. 



Our British Composites may be grouped under two 

 Tribes : Tubuliflora, with all the florets (Spear Thistle), 

 or those of the disk only (Daisy), 

 tubular ; and Liguliflorce, with all 

 the florets ligulate (Dandelion). 



The florets of Ligulifloras are 

 all perfect, i.e. they each contain 

 both stamens and pistil. 



The florets of Tubuliflorae may 

 be either all perfect (Spear 

 Thistle); or the outermost 

 florets may be neuter (Corn 

 Centaurea, or Bluebottle), or 

 pistillate (Daisy or Chamomile) ; 

 or the florets may be monoe- 

 cious, those of the disk being FIG. 117. Vertical section of 

 staminate, those of the ray pis- { S^enuu. 



tlllate (Common Marigold, Cal- one disk-floret being left. 



endula)\ or the flower-heads may 



be dicecious (Mountain Cudweed, Gnaphalium dioicum). 



If all the florets of a flower-head (capitulum) be per- 

 fect, the flower-heads are homogamous (Dandelion, SOW- 



FIG. 1 1 8. Vertical section through flower-head of Sowthistle. 



thistle) ; if part of them be imperfect, the heads are 

 heterogamous (Daisy). 



