CHICORY FAMILY 279 



Leaves linear-lanceolate, perfectly entire. 3. L. polyphylla. 



Leaves pinnatifid or lobed, at least some of them. 4. L. canadensis. 



Involucres 1.2-2 cm. high. 



Leaves obovate or oblanceolate in outline, with broad lobes, often spinulose 



on the midribs beneath. 5. L. ludoviciana. 



Leaves linear or linear-lanceolate in outline, entire or with narrow lobes, 

 never spinulose. 6. L. qraminifolia. 



Bracts in 5-6 series, gradually increasing upwards, a distinct calyculuih therefore not 

 evident; flowers blue. 7. L. pulchella. 



Achenes beakless; pappus tawny or brown. 



Lobes of the leaves broadly triangular or ovate, sinuately and saliently dentate. 



8. L. s'picata. 

 Lobes of the leaves lanceolate or linear, again 1-3-Iobed. 9. L. mullifida. 



26. SONCHUS (Tourn.) L. Sow-thistle. 



Perennial: achenes slightly compressed; involucres usually glandular-pubescent; heads 

 about 2 cm. liigh. 1. S. arvensis. 



Annual; achenes strongly compressed; Involucres usually glabrous; heads about 15 mm. 

 high. 

 Auricles of the leaves acute; achenes transversely wrinkled. 2. S. oleraceus. 



Auricles of the leaves rounded; achenes not transversely wrinkled. 3. S. asper. 



