LiATRis. COMPOSITiE. 77 



achenia minutely pubescent. — Willd. ! spec. 3. p. 1637; Michx. ! I.e.; 

 Pursh, I. c. ; Nutt. ! ^en. 2. p. 132 ; Ell. sk. 2. p. 283 ; DC! I. c. Anony- 

 mos paniculatus, Wait,.! Car. p. 198. 



Moist pine barrens, Virginia to Florida! common. Sept.-Oct. — Stem 1-2 

 feel high, virgale, purplish, somewhat villous or hirsute with glutinous hairs. 

 Cauline leaves very small, a])pressed, almost imbricated. Heads as large 

 as in the preceding species. Corolla purple, sometimes almost white. The 

 scales of the involucre vary from 6 to 16, and the flowers from 4 to 10. 



L. flexnosa of D. Thomas, in Sill. jour. 27. p. 338 (1839), is either L. cylin- 

 dracea or a reduced L. squaiTosa ; it is impossible to determine which from the 

 imperfect description and figure. 



12. CLAVIGERA. DC. prodr. 5. p. 127. 



Heads 5-20-flowered. Scales of the involucre imbricated in several series, 

 striate ; the exterior very short ; the innennost elongated, linear. Receptacle 

 narrow, naked. Corolla tubular, dilated at tlie base, not expanded above, 

 5-toothed ; the teeth very short, glandular externally. Style with a villous 

 bulb at the base ; the branches terete or subclavate, mostly glabrous, included 

 or partly exserled. Achenia somewhat cylindrical, striate (mostly 10-striate), 

 nearly glabrous, sessile. Pappus a single series of plumose-barbellate bris- 

 tles. — Somewhat shrubby branched (Mexican & Texan) plants. Leaves 

 alternate, 1 -nerved or tripli-nerved, linear or oblong, entire or toothed, some- 

 times dotted with resinous globules, or punctate. Heads in a corymbose or 

 spicate panicle. Flowers whitish. 



" A genus intermediate between Kuhnia and Liatris [but much nearer the for- 

 mer], dedicated, on account of the species being all natives of Mexico, to Franc. 

 Xav. Clavigero, who wrote upon the natural as well as the civil history of Mexico." 

 DC. — On the authority of Hrenke's herbarium, De Candolle gives Mulgrave Sound 

 as one of the localities of C. scoparia ; but this is probably a mistake; and much 

 confusion is said to exist respecting the localities of Hsenke's plants. 



1. C. dcntata (DC.) : pubescent, cinereous, shrubby ; leaves oval-oblong, 

 toothed, here and there .somewhat lobed at the apex ; branchlets leafy, bear- 

 ing one or few heads disposed in a narrow panicle; heads l2-fl()wered; scales 

 of the involucre linear-lanceolate, acuminate, ciliate, somewhat scarious at 

 the apex, more or less striate. DC. I. c. 



Texa.s, in the eastern districts (Cammancheries), and about Bexar, Ber- 

 landier, ex DC. — This species jterhaps hardly conies within the prescribed 

 limits of our Flora. We introduce it for comparison with the following, 

 apparently different, species. 



2. C. Riddellii : shrubby; the branches cinereous and miinitely pubes- 

 cent: leaves oblong-lanceolate, okscurely punctate ; the lower ones tripli- 

 nerved, reticulate-veined beneath, minutely pubescent, unequally serrate; 

 those of the branches small, crenaiely toothed from the middle to the 

 apex; heads 15-20-fiovvere(l, disposed in a leafy spike or thyrsus terminating 

 the virgate branches; scales of the involucre pubescent and glandular, stri- 

 ate, obtuse, seldom mucronate; the exterior ovate; the inner lanceolate- 

 linear, slightly scarious at the apex. 



Interior of Texas, Dr. Riddell ! — A much branched shrub, 4-6 feet high. 

 Lower leaves slightly petioled. Spike or raceme nearly simple, dense, vir- 

 gaie ; the hemls .scarcely exceeding the leaves from the axils of which ihey 

 arise, the lower ones flowering earliest. Branches of the style partly ex- 

 serted, clavate. Achenia about 10-striate. 



