38 



ELEMENTS OF STRUCTURAL BOTANY. 



48. It appears, then, that the Dandehon, instead 

 of being a single flower, is in reahty a compound 

 of a great many flowers upon a common reccp- 

 iii tacle, and what seemed at first to he a calyx is, in 

 Fig. 55. reality, an involucre, made up of many bracts. 



But have the single flowers, or florets, as they are 

 properly called, no calyx ? The theory is that they 

 have one, but that it is adherent to the surface of the 

 ovary, and that the tuft of silky hairs which we noticed 

 is a prolongation of it. 



Now turn to your specimen having the seeds ready to 

 blow away. The seeds are all single ; the 

 little bit of stalk at the top has grown into 

 a long slender thread, and the tuft of hairs 

 has spread out like the rays of an umbrella 

 (Fig. 56). But though the seeds are inva- 

 riably single, it is inferred from the two- 

 lobed stigma that there are two carpels. 



49. Flowers constructed on the plan of 

 the Dandelion are called composite flowers. 

 A very large number of our common plants 

 have flowers of this kind. The May-weed, which 

 abounds in waste places everywhere, the Thistle, and 

 the Ox -Eye Daisy are examples. 



DANDELION. 



Fig. 56. 



