856 COMPOSITAE (COMPOSITE FAMILY) 



lucre glabrous ; bracts straightish, lance- to linear-attenuate. (A. Lappa, var. 

 majus Gray; A. majus Bernh.) Roadsides and waste places, N. B., N. E., 

 and probably westw. (Nat. from Eu.) 



2. A. MINUS Bernh. (COMMON B.) Heads racemose or subracemusc, 1.5-3 

 cm. broad; involucre glabrous or arachnoid ; bracts shorter, more slcuiicr <IH<I 

 more arcuate than in the preceding. (A. Lappa, var. Gray.) Similar situa- 

 tions, too common throughout our range except on the northeastern borders 

 where largely replaced by the preceding. Including A. Lappa, var. tomen- 

 tosum Gray, a form differing only in its more or less arachnoid involucre, and 

 apparently less marked or characteristic than the European A. tomentosum Mill. 

 (Nat. from Eu.) 



81. ECHINOPS L. GLOBE THISTLE 



Heads 1-flowered, many, aggregated in dense globular capitate clusters, the 

 common involucre of small rettexed bracts. Proper involucres cylindrical, of 

 several series of unequal imbricated spinescent paleaceous bracts ; corollas with 

 slender tube and cylindric 5-parted limb. Filaments glabrous. Achenes cylin- 

 drical or somewhat tetragonal ; pappus coroniform or of many short distinct or 

 connate subpaleaceous bristles. Stately thistle-like herbs, with alternate spinose 

 pinnatifid or dentate leaves, and large globose terminal (compound) heads of 

 whitish or bluish flowers. (Name from ^x* ws hedgehog, and 6\f/is, appearance, 

 from the bristly nature of the armed foliage or perhaps of the spreading indi- 

 vidual heads in the dense spherical gloinerules.) 



1. E. SPHAEROCEPHALUS L. Tall, 1-2 m. high, grayish- or white-arachnoid 

 on the stem and lower surface of leaves. Frequent in cultivation and not rare 

 as an escape upon waste-heaps, etc. (Introd. from Eu.) 



82. CARDUUS [Tourn.] L. PLDMELESS THISTLE 



Bristles of the pappus naked (not plumose), merely rough or denticulate. 

 Leaves conspicuously decurrent, spiny; wings of stern spiny. Otherwise as in 

 Cirsium. (The ancient Latin name.) 



* Heads large, nodding, solitary on long nearly naked peduncles; involucre 



3-4 cm. in diameter. 



1. C. Ntn-ANsL. (MuSK THISTLE.) Biennial ; heads solitary, hemispherical, 

 3-5 cm. broad; bracts lanceolate, the outer reflexed ; flowers purple. Fields 

 near Harrisburg, Pa. ; also pastures, waste places, and ballast, n. to N. B. and 

 Que. June-Oct. (Nat. from Eu.) 



* * Heads smaller, chiefly clustered at the ends of winged branches ; involucre 



1-2.5 cm. in diameter. 



2. C. ACANTnolDEs L. Annual or biennial ; involucre hi-mixphrrical, 1.5-2.5 

 cm. broad; traces linear, the outer somewhat herbaceous and spreading ; flowers 

 rose-purple; corollas about 18 mm. long. Waste places and ballast, N. S. to 

 N. J. June-Aug. (Adv. from Eu.) 



3. C. CRfspus L. Annual or biennial ; heads mostly clustered and sessile or 

 nearly so; involucre ovoid, 1-1.3 cm. broad; bracts linear-attenuate, the <>m>r 

 rather rigid, hardly spreading ; flowers purple or white ; corollas about 14 mm. 

 long. Roadsides, Sydney, Cape Breton ; Philadelphia, Pa. ; and St. Louis, Mo. 

 Aug. -Sept. (Adv. from Eu.) 



83. CIRSIUM [Tourn.] Hill. COMMON or PLUMED TIIISTLK 



Heads many-flowm-d ; flowers all tubular, perfect and similar, rarely imper- 

 fectly dioecious. Bracts <>t the n\>id or spherical involucre imbricated in many 

 rows, tipped with a point or prickle. Receptacle thickly clothed with soft 

 bristles or hairs. Achenes oblong, flattish, not ribbed ; pappus of numerous 

 bristles united into a ring at the base, plumose to the middle, deciduous. 



