u8 COMPOSITE. [CHAP. 



comprises the Daisy (Bellis), Dandelion (Taraxacum), 

 Groundsel (Senecio), Chrysanthemum, Thistle 

 (Carduus), Lettuce (Lactuca), Hawkweed (Hieracium), 

 &c. Though there are many differences in the 

 structure of the flowers, as might naturally be 

 expected in so large a group, still in many respects, 

 they are very uniform. The florets are so closely united 

 on a common head, that each group is commonly, 

 though of course incorrectly, spoken of as a single 

 flower. The so-called flower of the Daisy, for instance, 

 is in reality a group of flowers ; the outer row of 

 which, or ray florets as they are termed, are unlike 

 the rest and terminate on the outer side in a white 

 leaf or " ray." 



The advantages of this arrangement are : 



1. That the flowers become much more conspicu- 

 ous than would be the case if they were arranged 

 singly. 



2. That the facility with which the honey is obtained 

 renders them more attractive to insects. 



3. That the visits of the insects are more likely to 

 be effectual, since the chances are that an insect which 

 once alights, touches several, if not many, florets. 



No wonder, therefore, that the Compositae are the 

 most extensive family among flowering plants, are 

 represented in every quarter of the globe and in 

 every description of station (Bentham, " Handbook 

 of the British Flora," vol. i. p. 408 ; Jour. Linn. 

 Soc. 1873, p. 335,) and contain nearly ten thousand 

 species. 



The principal differences among the Compositae, 

 regarded from the point of view of the present work, 



