COMPOSITE FAMILY. 255 



64. ARCTIUM, BUKDOCK. (Probably Greek, bear, from the spiny 

 involucre.) (p. 222.) 



A. Ldppa, Linn. COMMON B. Leaves large, loosely cottony beneath, 

 or somewhat naked, the lower heart-shaped, upper ovate ; common in 

 manured soil and barnyards. Var. minor is smaller and smoother, with 

 leaves tapering at the base, often cut-toothed or cleft. Flowers mostly 

 purple, all summer and autumn. (D 



65. CNICUS, THISTLE. (Old name.) Flowers purple or pink, 

 occasionally yellow or white, in summer. (D JJ. (pp. 221, 222.) 



* All the scales of the head armed with spreading prickly tips. 



C. lanceolatus, Hoffm. COMMON or BULL T. Nat. from Eu. in pastures ; 

 the base of the rough, deeply pinnatifid leaves running down the stem in 

 lobed prickly wings ; flowers purple. (2) 



* * All or most of the scales of the head appressed, the innermost not 

 prickly-pointed, the outer with a short prickle or point, or none. 



H- Leaves green both sides or a little cottony or cobwebby underneath. 



C. arvensis, Hoffm. CANADA T. A vile pest in fields and meadows 

 N., nat. from Eu. ; spreading by deep, running roots as well as by seed ; 

 numerous short-peduncled heads only 1' long, with rose-purple flowers ; 

 leaves moderately pinnatifid, weak-prickly. ! 



C. horrldulus, Pursh. YELLOW T. Leaves very prickly, rather large 

 heads surrounded at base by an involucre or whorl of leaf-like very 

 prickly bracts ; flowers yellowish or purplish. Sandy fields near the 

 coast, Mass., S. 



C. pumilus, Torr. 19-3 high, with lance-oblong pinnatifid leaves, 

 single very large heads (almost 2' across) of fragrant (purple or rarely 

 white) flowers, sometimes leafy-bracted at base. Me. to Pa. (2) 



C. muticus, Pursh. Swamps and low ground ; 3-8 high, with 

 deeply divided leaves, few or no prickles, and rather large naked heads, 

 most of the scales pointless ; flowers purple. 2/ 



-- i- Leaves white-cottony underneath; flowers purple, rarely white. 



C. altlssimus, Willd. 3-10 high, branching, leafy up to the rather 

 small heads, the oblong leaves wavy or only slightly pinnatifid, except the 

 lowest. @ % Mass, to Minn., S. 



Var. discolor, Gray. 3-6 high, branching and leafy, with rather 

 small heads, and deeply pinnatifid leaves, green above, white beneath, 

 their lobes narrow and prickly pointed. (2) 



C. Virginianus, Pursh. Stems rather simple, l-3 high, ending in a 

 long naked peduncle ; leaves lanceolate and slightly or not at all pinnati- 

 fid ; head small. 2Z Plains and barrens, Va., W. and S. 



66. CYNARA, ARTICHOKE. (Ancient Greek name.) 2/ (p. 222.) 



C. Cardunculus, Linn. CARDOON. Leaves deeply and compoundly 

 divided and prickly, the less fleshy scales of the head prickly-tipped ; the 

 fleshy leafstalks and midrib eaten after being blanched in the manner of 

 celery. Strong thistle-like plants, 4-6. Eu. 



C. SCOLYMUS, ARTICHOKE, has less compound leaves, the ovate and 

 usually pointless scales of the involucre and the receptacle of the young 

 flower heads fleshy, and edible when cooked. A modification of the 

 above. 



