PHANEROGAMIA 



597 



upper lip, it becomes one-lipped or falsely ligulate (Fig. 591, a), 

 as in the marginal flowers of the Chrysanthemum ; or it is ligulate 

 and split for a considerable distance on one side, as in Tiinuacinn 

 (Fig. 593, 2). The one-lipped and ligulate flowers are very similar in 

 appearance, but in the one-lipped flowers the corolla has only three 

 teeth, in the ligulate five. The margin of the receptacle is frequently 

 occupied by one-lipped flowers, and the central portion or disc by 

 actinomorphic tubular flowers. In such cases it is customary to 

 distinguish between ray-flowers and disc-flowers. The former are 

 frequently female {Arnica, Inula, Matricaria) or neuter (Ueiitaurea 

 Oyanus) ; the disc-flowers are sometimes all male (Tussilago). The 

 style divides at the apex into two variously shaped stigmas, and is 

 surrounded at the base by a honey-secreting disc. The fruit 

 (Fig. 592, b) is a one-seeded indehiscent fruit or achene; it is usually 



Fig. 5HB.— Taraxacum ojiriuab: 1, Two capitula and a leaf; i, a flower ; 3, fruit ; 4, receptacle with 

 one fruit.— Officixa l. (After Wossidlo.) 



crowned by a pappus which is of service in the dissemination of the 

 seeds by the wind. The pericarp is leathery, and often adherent to 

 the oily seed. 



Sris- Families, Tribes, and Representative Genejia. — (1) Tulmlifiorae. 



