572 



DICOTYLEDONES. 



tubular corollas (Fig. 610). Sometimes only tubular flowers are 

 present, as e.g. in Senecio v^dgaris (Groundsel), and the exterior 

 of the capitulum is then as in the Eupatoriere. The stylar 

 branches are straight, more or less flat and short (Fig. 610). 



A. ANTHEMIDE.E. Involucral leaves imbricate, generally mem- 

 branous at the edge ; pappus -wanting, or at most a membranous 

 margin to the calyx, but without hairs. 



f. Chaff-like bracts on the receptacle are found in Anthemis 

 (Chamomile), Anacydus (A. officinarum) , Achillea (Milfoil, Fig. 610), 

 Saiitolina, etc. 



ft- A naked receptacle is found in the following: Bdlis 

 (Daisy) has solitary capitula on leafless stalks with white ray- 

 flowers. Matricaria (Wild Chamomile) has a conical receptacle. 

 (M. chnmomilla has a ver^ high, hollow receptacle; 31. inodora Las large, odour- 

 less capitula, and the receptacle is not hollow.) -- Chrysanthemum (Ox- 

 eye) most frequently large, solitary capitula; flat receptacle. - 

 Pi/rethrum; pappus scanty. With these are classed Tauacetum 

 (Tansy) and Artemisia (Wormwood) with tubular corollas only. 



B. HELIANTHE^. Most frequently a bract to each flower is 

 found on the receptacle. The pappus is never exactly hairy, but 

 consists of scales, spines, etc., and the fruits are most frequently 

 compressed (Fig. 606 c).He!ia>ithus (Sun-flower) ; H. tuberosus 

 (Jerusalem Artichoke) has tuberous underground stems. Dahlia 

 has tuberous roots (Am.). Bidens (Bur-marigold, Fig. 606 c) ; the 

 fruits are compressed Avith 2 (or more) spines provided with 

 reflexed barbs. Calliopsi*; Rudbeckia; Zinnia; Tagetes has united 

 involucral leaves, and yellow, transparent oil-glands. Spilanthes, 

 Galinsoga, Melampodium, Silphium (Compass-plant), Heleniimi, 

 GaiUarJui. 



C. CALENDULE.E have 1-2 rows of involucral leaves, a naked 

 receptacle, and large, crescent-shaped, irregularly warted fruits, 

 of different forms in the same capitulum ; pappus absent (Fig. 

 605). Calendula (Marigold); ray-flowers ?, disc-flowers ^ . 



D. SENECIONE^E, have a fine, hairy, white pappus; no bracts, 

 otherwise as in Anthemidere. The involucral leaves are most 

 frequently in 1-2 rows. Senecio (Groundsel) has two whorls 

 of involucral leaves, which most frequently have black tips, the 

 external being much shorter than the internal ones (8. vulgaris 

 has all flowers $ and alike). CacaUa, Doronicum, Cineraria, 

 Ligularia, Arnica (A. montana ; large, long-stalked capitula ; leaves 

 opposite, forming a kind of rosette). 



