CL. XIX.] SYNGENESIA POLYGAMIA ^QTJALIS. 317 



short weak thorns : leaves woolly beneath : scales of the calyx 

 purple,^keeled near the end with a soft shining substance : flowers 

 purple. Biennial : flowers in July : grows in moist meadows, by 

 ditches and pools : frequent. Eng. Bot. vol. xiv. pi. 974 : Carduus 

 palustris. Eng. FL vol. iii. p. 388. 1156. 



** Leaves not decurrent. 



7. C. arve'nsis. Field Thistle. Leaves sessile, pinnatifid, thorny ; 

 stem panicled ; calyx egg-shaped, with closely-pressed, minutely 



thorn-pointed scales. Stem from two to four feet high, round, 



smooth, angular: leaves bare beneath : flower-stalks cottony: flowers 

 pale-purple. Perennial : flowers in July : grows in corn-fields, pas- 

 tures, and waste places: common. Eng. 5oi.vol.xiv.pl. 975. 1157. 



8. C. eriophorus. Woolly -headed Thistle. Leaves pinnatifid, with 

 thorny segments pointing two ways, bristly above ; calyx globular, 



densely woolly, with minutely thorn-pointed scales. Stem three 



feet high, furrowed, slightly hairy : flowers numerous, very large, 

 purple. Biennial: flowers in August: grows by roads and in dry- 

 pastures : not common. Eng. Bot. vol. vi. pi. 386. Eng. FL vol. iii. 

 p. 390. 1158. 



9. C. tuberosus. Tuberous Thistle. Leaves deeply pinnatifid, 

 lobed, fringed with prickles, the lower ones stalked; stem smooth, 

 almost one-flowered ; scales of the calyx minutely thorn-pointed, 



nearly smooth ; root creeping, tuberous. Stem two feet high, 



erect, straight, furrowed, hairy : flower erect, bright-purple. Pe- 

 rennial : flowers in August. Found by Mr. Lambert in a thicket 

 on the Wiltshire downs. Eng. Bot. vol. xxxvi. pi. 2562. Eng. Fl. 

 vol. iii. p. 391. 1159. 



10. C. heterophy'ttus. Melancholy Thistle. Leaves embracing the 

 stem, lance-shaped, fringed, undivided or pinnatifid, smooth on their 

 upper side, densely cottony beneath ; stem downy, almost one- 

 flowered. Stem three feet high, erect, hollow, cottony, bearing 



a single large purple flower. Perennial : flowers in July and Au- 

 gust : grows in moist pastures in Scotland, Wales, and the north of 

 England : frequent. Eng. Bot. vol. x. pi. 675 : Carduus heterophyllus. 

 Eng. Fl. vol. iii. p. 392. 1160. 



11. C.pratensis. Meadow Thistle. Leaves sessile, lance-shaped, 

 waved, fringed with unequal thorns, cottony beneath; stem downy, 



one-flowered ; calyx cottony, its scales lance-shaped. Stem about 



a foot high, furrowed, bearing a single pale-purple flower. Peren- 

 nial : flowers in June and July : grows in. moist pastures : not 

 common. Eng. Bot. vol. iii. pi. 177 : Carduus pratensis. Eng. Fl. 

 vol. iii. p. 393. 1161. 



12. C. acaulis. Dwarf Thistle. Scape one-flowered, shorter than 



the smooth calyx. Leaves oblong, pinnatifid, spreading close to 



the ground : flower almost sessile, large, purple. Perennial : flowers 

 in July : grows in dry pastures in England : common in some 

 places. Eng. Bot. vol. iii. pi. 161. Eng. Fl. vol. iii. p. 394. 1162. 



17. ONOPO'RDUM. COTTON-THISTLE. 



Common calyx roundish, tumid, imbricated, of numerous 

 lance-shaped, thorn-pointed scales, permanent. Compound 

 corolla uniform, with, very numerous, equal, funnel-shaped 

 corollas ; their tube very slender ; the limb deeply divided into 

 five linear, equal segments. Filaments hair-like, very short ; 



