232 COMPOSITE. (COMPOSITE FAMILY.) 



2. A. nudicailliS, Ell. Hairy and rather glandular (l-3high); 

 leaves tliiclcish, 3-5-nerved, ovate or olilong, all sessile, mostly entire; those of the 

 nakid stun small and only 1 or 2 pairs; heads several, corymbed, showy. 

 Damp pine barrens, Virginia and southward. April, May. 



65. CENTAUREA, L. STAR-THISTLE. 



Heads many-flowered ; the flowers all tubular, the marginal mostly falsely 

 radiate and larger, sterile. Receptacle bristly. Involucre imbricated, the scales 

 margined or appcndaged. Achenia compressed. Pappus wanting, or of a few 

 bristles. Herbs with alternate leaves and single heads. (Named from the 

 Centaur, Chiron.) 



1. C. CYANUS, L. (BLUEBOTTLE.) Scales of the globular involucre 

 fringe-margined ; fake rays large, pappus very short ; leaves linear, entire, or 

 toothed at the base. Road-sides, escaped from gardens. July. Flowers 

 blue, varying to purplish or white. (Adv. from Eu.) 



2. C. NIGRA, L. (KNAPWEED.) Scales of the globular involucre appen- 

 dagcd, and with a stifF black fringe ; rays wanting ; pappus very short ; leaves 

 lanceolate, or the lower lyrate-anglcd, rough. 1J. Waste places, E. New Eng- 

 land. Aug. Flowers purple. (Adv. from Eu.) 



3. C. CALcfTRAPA, L. (STAR THISTLE.) Stem diffusely much branded ; 

 leaves pinnuJLcly loled or spinulose-toothed ; heads sessile, the middle scales of the 

 ovoid involucre spiny ; pappus none ; flowers purple. (3) Norfolk, Virginia. 

 (Adv. from Eu.) 



C. AMERIC\NA, Nutt., a showy species of the Southwestern States, the 

 only one which belongs to this country, is cultivated in gardens. 



66. C NIC US, Vaffl. BLESSED THISTLE. 



Heads many-flowered ; the ray-flowers tubular and sterile, shorter than the 

 rest, which arc all tubular and perfect. Scales of the ovoid involucre coriaceous, 

 appresscd, extended into a long and rigid pinnately spinose appendage. Re- 

 ceptacle clothed with capillary bristles. Achenia terete, short, strongly striate, 

 crowned with 10 short and horny teeth, and bearing a pappus of 10 elongated 

 ri^iil bristles, and 10 short bristles alternate with the lost in an inner row. An 

 annual smoothish herb, with clasping scarcely pinnatilid-cut leaves and largo 

 bractcd heads. Flo\ycrs yellow. (Name from xvifa, to prick.) 



I. C. BEXEDfcTus, L. Road-sides ; scarcely naturalized. (Adv. from Eu.) 



67. CIRSIUrtf, Tourn. COMMON or PLUMED THISTLE. 



II -nds many-flowered ; the flowers all tubular, perfect and similar, or rarely 

 imperfectly din-clous. Scales of the ovoid or spherical involucre imbricated in 

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

 soft bristlis or h:tirs. Aehenia oblong, flattish, not ribbed. Papp is of nmncr- 

 ourt brii*il-s united into a ring at the base, plumose to the middle, deciduous. 



