COMPOSITE FAMILY 239 



100. COMPOSITE. CoMPosiTi: Family 

 Flowers epigynoiis, in a dense head, on a common recepta- 

 cle, surrounded by an involucre composed of many bracts 

 (Fig. 29), with usually 5 stamens inserted on the corolla, 

 the anthers united into a tube which surrounds the style. 



Fig. 29. Flower chister and flowers of yarrow 

 A, flower cluster; B, section of flower cluster; C, a ray flower ■ J) a disk 

 flower rt. anthers ; ch, chaff of disk ; cf, disk flowers ; o, ovary ;yr 'crolias 

 of ray flowers ; 5, stigmas ; tc, corolla of tubular flower. (A, B, C, 7 times 

 natural size; D, 18 times natural size) 



Calyx with its limb sometimes wanting; when i)resent taking 

 the form of scales, bristles, etc., known as paj^pus (Fig. aO). 

 Corolla either strap-shaped (Fig. 29, rr) or tubular (Fig. 29, fc); 

 in the former case often 5-toothed, in the latter usually 5- 

 lobed. Style 2-cleft above. Fruit an akene, often provided 

 Avith means of transportation. This is the largest family of 

 flowering plants and among the most specialized for insect 



