COMPOUND FLOWERS 



157 



3. L. saligna (Willow Lettuce). — More slender than the last, 

 leaves narrower, and perpendicular against the stem ; variable and 



, likely to be confounded with L. scoriola. Rare ; confined in 

 Britain to chalky situations, in the south-east, near the coast. — Fl. 

 July, August. Biennial. 



4. L. Alpina (Alpine Lettuce, or Blue Sow-thistle). — A handsome 

 erect, unbranched plant 2-3 feet high, with a panicle of large blue 

 flower-heads. It grows on the Clova Mountains, but is rare. Per- 

 ennial. Known also as Sonchus Alphms. The Garden Lettuce 

 (L. sativa) belongs to this genus, but is not a native plant. 



8. Sonchus {Sow-thistle) 



1. S. oleraceus (Common Sow-thistle, 

 Milk-thistle). — Erect, branched, 1-4 

 feet high ; stems hollow ; leaves oblong, 

 more or less pinnatifid or entire, 

 toothed, often prickly, the upper ones 

 often clasping the stem with spreading, 

 arrow-shaped auricles ; heads some- 

 what umbellate ; involucres smooth. 

 Waste places, and as a garden weed ; 

 common. This plant makes light and 

 salutary meals for rabbits. — Fl. June to 

 September. Annual. 



2. S. arvensis (Corn Sow-thistle). — 

 Stem simple, 2-4 feet high, tubular, 

 angular ; leaves oblong, pinnatifid or 

 wavy, toothed and spinous. The lower 

 ones stalked and heart-shaped at the 

 base; upper clasping the stem withiConpiion Sow-thistle, Milk-ihistle) 

 auricles ; loose corymbs of large yellow 



flower-heads ; involucre and flower-stalks with dark glandular 

 hairs. In similar situations with the last, from which it may be 

 readily distinguished by its simple stem and much larger flowers. 

 ^Fl. August, September. Perennial. 



3. S. palustris (Marsh Sow-thistle).— Much resembhng the last, 

 but taller ; stem 6-8 feet high, unbranched ; leaves long, narrow, 

 clasping the stem with pointed auricles ; flower-heads large, pale 

 yellow ; involucres with glandular hairs. " Marshes in the south- 

 east of England ; very rare. 



A variety of S. oleraceus, frequently found growing with it, is 

 S.rts/)e>-(RoughSow-thistle).— The ;gat)^sare;morespinously toothed, 

 with rounded auricles, and darker in colour, whilst the longi- 

 tudinal ribs of the achenes are not transversely wrinkled. 



SoNCHOs Oleraceus 



