II COMPOSITE 235 



EUPATORIUM 



Flower-heads of few florets. Protandrous. The 

 branches of the stigma are as long as the flower-tubes, 

 and for three-quarters of their length clothed with hair. 



E. cannabinum (Hemp Agrimony). — The plant is 

 so named from the form of the leaves. There are 

 generally only about 5 florets to a head. They are of a 

 reddish purple, and as the flower-heads themselves are 

 numerous and in compact terminal corymbs, they are 

 very conspicuous in spite of the small size of the indi- 

 vidual florets. The corolla tube has a length of 

 4|- mm., of which 2-g- form a tube and the upper 2 are 

 expanded into a bell. The anther tube does not pro- 

 ject beyond the bell of the corolla. The anthers open 

 on the inner side, and the pollen fills the upper part of 

 the tube. When the flower opens the upper part of the 

 branches of the pistil elongate and carry up the pollen 

 on their hairy surface. The lower parts constituting 

 the stigma are still in the corolla. In the second stage 

 of the flower the papillary part of the stigma also pro- 

 trudes and is ready for fertilisation. The long pollen- 

 covered hairy branches of the stigma must often serve 

 to fertilise neighbouring florets. 



TUSSILAGO 



T. Farfara (Coltsfoot) has the flower-heads solitary 

 and yellow ; while in T. Petasites they form a com- 

 pound raceme, and are white or pinkish. The flower 

 was well described by Sprengel. It is monoecious. 

 The ray flowers are female ; those of the disk, male ; 

 both being yellow. The pistil of the ray flowers 

 has a pollen brush, which would appear to be use- 

 less, and in most Composites is not developed in the 

 female flowers. The male flowers are about 40, the 

 female about 300 in number. The male flowers only 

 produce honey. The flower-heads close up at night 

 and in bad weather. Burkill ^ remarks that the female 



' Jmirnal of Botany, 1897. 



