186 COMPOSITE FAMILY. 



§ 4. Pappus of extremely copious and fine soft hair-like naked bristles. 

 * Mature akenes with the pappus raised on a very long slender stalk-like beak. 



71. PYRRHOPAPPUS. Head of yellow flowers as in the next; but the pappu3 



rusty red and with a minute ring of soft down underneath it. Stems branch- 

 ing and leafy near the base, the long peduncles naked. 



72. TARAXACUM. Head of very many yellow flowers on a slender hollow and 



wholly naked scape. Involucre double, the inner of numerous narrow scales 

 in a single row, the outer of short loose scales. Akenes terete or spindle- 

 shaped, strongly ribbed and tubercled on the ribs, much shorter than its 

 slender beak which elevates at maturity the soft and white pappus. (Les- 

 sons, p. 130, fig. 296.) 



73. LACTUCA. Heads of several variously colored flowers. Involucre of several 



lanceolate or ovate imbricated scales of unequal length. Akenes flat, ab- 

 ruptly contracted into the slender beak which elevates the very white soft 

 pappus. Stems leafy. 

 « * Akenes with a short and thick beak or none : heads many-flowered. 



74. MULGEDIUM. Involucre as in 73. Flowers blue or bluish. Akenes flat- 



tened, short-beaked. Stems leafy. 



75. SONCHUS. Involucre as in 73, or with naiTow and more equal scales, and 



tumid at base. Flowers yellow. Akenes flat and short, without a beak to 

 support its very soft white pappus. Stems branching and leafy. (Lessons, 

 p. 130, fig. 295.) 



1. CYNARA, ARTICHOKE. (Ancient Greek name.) Two species oo- 

 casionally cult, from the Old World, as esculents, y. 



C. Scolymus, True Artichoke, with stout stems, slightly prickly 

 leaves mostly once or twice pinnatifid and cottony beneath, the ovate and usu- 

 ally pointless scales of the involucre and the receptacle of the young flower heads 

 fleshy, and edible when cooked. 



C. Cardunculus, Cardoon, has the leaves more 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. 



2. CIRSIUM, TRUE THISTLE. (Old Greek name.) Flowers purple 

 or pink, occasionally yellow or white, in summer. © ^ 



§ 1 . All the scales of the head armed with spreading prickly tips. 



C. lanceol^tum, Common Thistle. Nat. from Eu. in pastures, &c. ; 

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

 prickly wings ; fl. purple. @ 



§ 2. All or most of the scales of the head appressed, the innermost not prickljf- 

 pointea, the outer with a short prickle or point, or none. 



* Leaves green both sides or a little cottony or cobwebby underneath. 



C. arvense, Canada T. a vile pest in fields and meadows N., nat. from 

 Eu. : s]n'eading by deep running roots as well as by seed : numerous short- 

 pedunclcd heads only 1' long, with rose-purple flowers ; leaves moderately pin- 

 natifid, wcak-prickly. 2/ 



C. horridulum, Yellow T. Wild near the coast in sandy ground ; 

 has very prickly leaves, rather large heads surrounded at base by an involucre 

 or whorl of leaf-like very prickly bracts, and yellowish or purplish flowers. 



C. pumilum, Pasture T. Wild in dry fields, 1°- 3° high, with lance- 

 oblong pinnatitid leaves, single very large heads (almost 2' across) of fragrant 

 (purple or rarely white) flowers, sometimes leafy-bracted at base. ® 



C. muticum, Swamp T. Wild in swamps and low ground; 3° -8° high, 

 with deeply divided leaves, few or no ])rickles, and rather large naked heads, 

 most of the scales pointless ; flowers purple. ^ 



* * Leaves white-cottony underneath : flowers purple, rarely white. Wild species. 



C. altissimum, Ta ll T. Fields from Penn. and S. ; 3° - 10° high, branch- 

 ing, leafy up to the rather small heads, the oblong leaves wavy or only slightly 

 pinnatifid, except the lowest. (2) % 



