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BRITISH WILD FLOWERS. 
THE WELTED THISTLE. (C. acanthoides, Lin.) 
This species is very common in every part of Great Britain, and some botanists suppose it to be the national 
Thistle of Scotland, while others give that honour to the Milk Thistle, which is certainly a much handsomer 
plant, though it is more rare in Scotland. This species is very abundant in that country, and it has been known 
in some cases to attain the height of eight feet. 
THE SLENDER-FLOWERED THISTLE. (C. tenuiflorus, Curtis.) 
This plant is common in various parts of England, particularly on sandy soils. It is an annual, and produces 
its small heads of flowers in June and July. 
III.—THE SUCCORY TRIBE. 
Florets all ligulate and hermaphrodite. Receptacle scarcely fleshy.—Sap generally milky. 
GENUS NXNIY. 
THE SO W-TPIISTLE. (Sonchus, Lin.) 
Lin. Syst. SYNGENESIA JEQUALIS. 
Generic Character.— Involucrum oblong, imbricated, ovate at the base. Receptacle naked. Fruit striated longitudinally. Pappus 
short, sessile, hairy. (Dec.) 
Description, &c. —This genus contains some of the commonest and most troublesome of the British weeds. 
The common Sow-Thistle ( S. oleraceus) is particularly troublesome, as it continues flowering all the summer, 
and, of course, is continually ripeuing and scattering its seeds. The plant is an annual, and the stem abounds in 
a milky juice. There are many varieties of this species, and three other species which are considered distinct. 
Two of these have yellow flowers ; but the flowers of the third (ft. alpinus) are blue. The name of Sonchus is 
derived from a Greek word, signifying soft; in allusion to the pliability of the stems. 
GENUS XXXY. 
THE LETTUCE. (Lactuca, Lin.) 
IAn. Syst. SYNGENESIA iEQUALIS. 
Generic Character. —Involucrum oblong, imbricated ; scales membranous at the margin. Receptacle naked. Pappus stipitate, hairy, 
soft, fugacious. (Dec.) ' 
Description, &c.— The Wild Lettuce (L. virosa) bears considerable resemblance when in flower to the 
Sow-Thistle, but its stem is much more slender. It is a biennial, and it produces its small yellow flowers in 
August. This plant is very common on hedge banks and other waste places in various parts of England, 
particularly on clayey soils. The whole plant abounds in a milky juice, which has the same qualities as opium, 
and is frequently used instead of it. There are three other species, but they are comparatively rare, with the 
exception of the Wall Lettuce (L. muralis), which is frequently found growing on old walls. The name of 
Lactuca is derived from lac , milk ; in allusion to the abundance of milky juice found in all the plants belonging 
to the genus. 
