578 



PART IV. CLASSIFICATION. 



rounded by an epicalyx (Fig. 394 /c') formed of connate bracteoles : 

 calyx often plumose or bristly (Fig. 394 fc): corolla usually bila- 

 biate : stamens only four, the posterior one being suppressed : 

 ovary apparently dimerous, one carpel being more or less com- 

 pletely suppressed, unilocular, with one suspended ovule: seed 

 with endosperm: leaves decussate, exstipulate: flowers in a dense 

 capitulum surrounded by an involucre of bracts: the outer florets 

 are usually ligulate : the Receptacle may or may not bear scaly 

 bracts (palese) : fruit invested by the epicalyx which is cleft longi- 

 tudinally. 



Fto. 394. Flower of 

 Scabiosa (mag.) : / ovary; 

 k' epiculyx (long sect.) ; 

 fc calyx ; c corolla ; t sta- 

 men * ; n stigma. 



FIG. 395. Floral dia- 

 gram of Composite 

 (tubular floret). 



Fis. 396. Flower of Arnica (mag.). A Tubular floret from the centre (disc) (longitudinal 

 sect.). B Ligulate marginal floret (ray): /ovary; p pappus; c corolla; a anthers; st 

 stamen ; n stigma ; g style ; ovule. 



Dipsacus, the Teazle, has a calyx without bristles; the capitula of 

 Dipsacus Fullonum are used in finishing woollen cloth, for the sake of the 

 strong hooked spines of the paleae : D. si/lvestris is common on waste ground. 

 In the genus Scabiosa, the paleae, which are usually present, are not 

 spinous : in the sub-genus Asterocephalus, the epicalyx (or involucel) is 

 8-furrowed, and its projecting limb is dry and scarious ; S. Columbaria, 

 with a 5-lobed corolla, is common in dry pastures: in the sub-genus 

 Succisa, the limb of the 8-furrowed epicalyx is herbaceous ; S. succisa, with 

 a 4-lobed corolla, occurs in damp meadows: in the sub-genus Knautia, 

 there are no paleae but the receptacle is hairy, and the epicalyx is 4- 

 furrowed ; S. arvenais is common in fields. 



