CHAP. I.] DIPSACE^. 389 



ORDER CYI DIPSACE^.— THE TEASEL TRIBE. 



The principal genera belonging to this order 

 are Dipsacus, the Teasel, and Scabiosa, the Sca- 

 bious ; to which may be added a pretty little 

 annual called Knautia. The plants belonging 

 to this order bear considerable resemblance to 

 those included in Compositse, as they consist of 

 a head of florets seated on a common receptacle, 

 which is chafFy, and surrounded by an involucre. 

 The florets are also furnished with what may be 

 called a double calyx, the limb of the inner 

 part being cut into long teeth, and resembling 

 the pappus of the Composit^e. In the genus 

 Dipsacus, the most important plant is the Ful- 

 ler's Teasel {Dipsacus fullonum)^ in which the 

 receptacle is raised in the form of a cone, and 

 the chafl'y scales are hooked, and so strong, 

 that the flower-heads when dry are used for 

 preparing broad-cloth. The leaves of this plant 

 are opposite, and united at the base. The 

 florets have a four-cleft corolla, and four dis- 

 tinct stamens; differing in this respect de- 

 cidedly from the Compositae, which have five 

 stamens, the anthers of which are always united 

 into a tube. Dipsacus sylvestris might be easily 

 mistaken for a kind of Thistle ; but the differ- 

 ence will be seen at once by examining the 

 anthers of the florets. The DeviFs-bit Scabious, 



