COMPOSITE. 133 



51. CREPIS, L. 



C. runeina'ta, Torr. and Gr. Stem 1-2 feet high, gla- 

 brous. Radical leaves obovate-oblong to oblong-lanceolate, 

 with short lobes or teeth. Cauline leaves absent or very 

 small. Involucre pubescent, sometimes it and the upper 

 part of the scape glandular. N.W. 



52. PREffAN'THES, Vaill. RATTLESNAKE-ROOT. 



1. P. alba, L. (Nabalus albus, Hook.) (WHITE LETTUCE.) 

 Heads8-12-flowered. Pap pus deep cinnamon-coloured. Stem 

 2-4 feet high, smooth and glaucous, corymbose-paniculate. 

 Leaves triangular-halberd-shaped, or 3-5-lobed, the upper- 

 most oblong and undivided. Rich woods. 



2. P. altiss'ima, L. (Nabalus aUissimus.) (TALL WHITE 

 LETTUCE.) Heads 5-6-flowered. Pappus pale straw-coloured. 

 Stem taller but more slender than in No. 1, with a, long, leafy 

 panicle at the summit. Rich woods. 



3. P. raeemo'sa, Michx. (Nabalus racemosus, Hook.) 

 Heads about 12-nowered. Involucre and peduncles hairy. 

 Stem wand-like, smooth. Leaves oval or oblong-lanceolate, 

 slightly toothed. Heads crowded in a long and narrow 

 interruptedly spiked panicle. Pappus straw-colour ; flowers 

 flesh-colour. Shore of Lake Huron and south-westward. 



4. P. Mainen'sis, Gray. Leaves as in the last, but the 

 radical ones ovate and more abruptly narrowed to the short 

 petiole. Heads 8-12-flowered, persistently drooping on 

 slender pedicels. Atl. Prov. 



53. LYGODES'MIA. Don. 



L. jun'eea, Don. Much branched from the base, the 

 branches closely erect and rigid, rush-like, terminating in 

 erect heads of pinkish flowers. Leaves small, the lower 

 lance-linear, the upper scale-like. N.W. plains. 



54. TRO VIHO V Nutt. 



1. T. CUSpida'tum, Pursh. Scape a foot high. Leaves 

 lanceolate, tapering to a sharp point, entire, woolly on the 

 margins. Achenes beakless. N.W. prairies. 



