GOMPOSITvE-COMPOSITE FAMILY 



The great family of Composites, which contains one-tenth of 

 all the species of flowering plants in the world, is marvellously 

 equipped to win in the struggle for life. Its pre-eminence lies in 

 its ability to ripen more seeds to a stem than any other family, 

 and consequently it overcomes its neighbors and possesses the 

 earth by sheer force of numbers. The top of the flower stem is 

 flattened and forms a platform, called the receptacle, upon which 

 the individual flowers are set, often to the number of hundreds 

 These are either tubular or ray flowers, or both. 



In the tubular flowers the calyx-tube is so united to the one 

 celled ovary as to be separate only at the summit where the calyx 

 border, technically called a pappus, appears in the form of bristles, 

 awns, scales, teeth, a minute cup, or nothing. The coroUa tube 

 is small, slender, five-lobed; the lobes valvate in the bud. The 

 stamens are five; the anthers unite to form a tube surrounding the 

 style, from which it finally protrudes. The style is two-cleft at the 

 apex. The fruit is a seed-like akene, crowned, usually, with the 

 remnants of the calyx-tube which appear so often in the form of 

 white bristles that they are called pappus; Greek for grand- 

 father. 



In the ray-flowers the corolla is strap-shaped and the strap often 

 has five minute teeth at the apex. The ray-flowers may be stami- 

 nate, pistillate, or perfect; the tubular-flowers are usually perfect. 

 The Composite flower-heads appear in three forms; that of which 

 the Sunflower is an example consists of a disk of tubular-flowers 

 and a row of rays about the edge ; this is a radiate head. A flower- 

 head consisting wholly of rays also is radiate, of which the dande- 

 lion is an example. A flower-head consisting of tubular-flowers 

 and no rays is called discoid, of which the Eupatoriums and the 

 Greenhouse Stevia are examples. 



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