BRITISH WILD FLOWERS. 
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GENUS XXIY. 
THE BUR-MARIGOLD. (Bidens, Lin.) 
Lin. Syst. SYNGENESIA HiQUALIS. 
Generic Character. —Involucrum with bracteolie at the base; j or hermaphrodite. Receptacle flat, paleaceous. Pappus from two to 
outer scales longer than the rest, and spreading. Flowers mostly flos- five persistent awns. ( Lindley .) 
cular ; florets all hermaphrodite, or if ligulate in the ray, then female, | 
Description, &c. —There are only two British species belonging to this genus, and both are annual plants, 
producing their bright yellow flowers in August and September. The plants are extremely acrid, and they are 
found abundantly in ditches and other moist places in various parts of England. The name of Bidens is derived 
from bis, double, and dens , a tooth; in allusion to the two teeth which crown the fruit. 
II.—THE THISTLE TRIBE. 
Ray none. Involucre conical and rigid. 
GENUS XXY. 
THE COTTON-THISTLE. (Onopordum, Lin.) 
Lin. Syst. SYNGENESIA .EQUALIS. 
Generic Character. —Involucrum imbricated ; scales pungent. Receptacle excavated like honey-comb. Fruit compressed, four-cornered, 
furrowed transversely. ' Pappus hairy, deciduous; its hairs connected in a ring at the base. {Lindley.) 
Description, &c. —There is but one species in this genus (0. Acanthium, Lin.) ; and this plant, which is 
very common on road-sides and hedge-banks wherever the soil is gravelly, is supposed by some botanists to be 
the true Scotch Thistle. It is easily known from the other kinds of thistle by the shape of its flowers ; the 
involucrum forming one large ball, and the head of flowers a smaller ball fixed on the top of the other. The 
florets are purple. The leaves are covered on both sides with a dense cottony web, which renders them quite 
white, but which is easily detached by rubbing it with the finger. The receptacle is very succulent, and it was 
formerly used for food like that of the Artichoke, though it is easily distinguished from that plant by the part 
vulgarly called the choke, consisting of much broader scales, and being so arranged as to form a kind of honey¬ 
comb; this peculiarity being, in fact, the distinctive mark of the genus. The seeds of this plant contain an immense 
proportion of oil, and birds are remarkably fond of them. The plant is a biennial, and it flowers in August. 
GENUS XXVI. 
THE SAUSSUREA. (Saussurea, Dec.) 
Lin. Syst. SYNGENESIA iEQUALIS. 
Generic Character. Involucrum imbricated ; scales unarmed. Florets all hermaphrodite. Receptacle paleaceous. Pappus in two 
rows, hairy ; the outer hairs short, with minute notches ; the inner long and feathery. {Dec.) 
Description, &c. —There is only one species in this genus, and even that was formerly included in Serratula, 
from which it has been separated on account of the slight difference in the pappus and in the anthers. The plant 
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