Lxxi. composit.t:. 37 



27. XANTHIUM, Linn. 



Annual coarse rough herbs unarmed, or with 3-fid spines. Leaves 

 alternate, toothed or lobed. Heads monoecious ( $ and g ), axillary, 

 the ^ in the upper axils, globose, many-flowered, sterile, tubular, 

 S-tootlied, the $ 2-flo\vered, apetalous, fertile. Heads of ^ flowers : 

 Involucre short ; bracts few, 1-2-seriate, narrow. lieceptacle cylindric, 

 with hyaline cuneate or linear-spathulate palese enclosing the flowers. 

 Corollas tubular, enlarged into a 5-toothed limb. Anthers distinct, 

 bases obtuse, tips mucronate, inflexed ; filaments monadelphous. Style 

 undivided, slender, slightly dilated at the apex. Achenes rudimentary. 

 Heads of § flowers : Invol.-bracts united into an ovoid 2-beaked 

 herbaceous 2-celled utricle (with 1 flower in each cell), enlarging iu 

 fruit, with hooked bristles and with sometimes a few small free outer 

 bracts. Corollas 0. Style-arms exserted from the beaks of the in- 

 volucre. Pappus 0. Achenes completely enclosed in the indurated 

 cells of the enlarged involucre (like seeds iu a capsule), compi-essed, 

 obovoid, thick. — Histrib. Species 4 of uncertain origin, but probably 

 all American. 



1. Xanthium strumarium, Zmn. fSp. PI. (1-753) p. 987. Annual, 

 unarmed ; stem short, stout, slightly branched, rough with short hairs. 

 Leaves numerous, 2-3 in. long and almost as broad as long, broadly 

 triangular-ovate or suborbicular, acute, often 3-lobed, rough with ap- 

 pressed hairs on both sides, irregularly inciso-serrate, somewhat cordate 

 and shortly cuneate at the base ; petioles 1-3 in. long, hairy. Heads in 

 terminal and axillary racemes, the barren heads rather numerous, crowded 

 at the top of the stem, the fertile heads fewer, axillary. Involucre of 

 fertile heads ovoid in fruit, about | in. long, with 2 erect mucronate 

 beaks, pubescent, thickly clothed with usually hooked prickles, 2-celled, 

 hard and tough. Achenes g in. long, oblong-ovoid, compressed, glabrous. 

 El. B. L V. 3, p. 303 ; C. B. Clarke, Comp. Lid. p. 132 ; Oliver, Fl. 

 Trop. Afr. v. 3, p. 371 ; Trim. Fl. Ceyl. v. 3, p. 35 ; Woodr, in Journ. 

 Bomb. Nat. v. 11 (1898) p. 649 ; Watt, Diet. Ecou. Prod. v. 6, part 4, 

 p. 318. Xanthium indicnm, DC. in Wight, Contrib. p. 17 ; Grab. Cat. 

 p. 101; Dalz. & Gibs. p. 127. — Elowers : Jan.-Eeb. Verk. SJian- 

 Jceshvar. 



KoNKAN : Stocks'., Law] ; Bombay below Parel flagstaff, (rrr/^a???. Deccan : Poena, 

 Cooke !, Woodrow ! ; banks of JVloola river, Kirkee, J. G. Woodrow ! ; Gokak Falls, 

 liitvhie, 1812 ! — Distrib. Throughout India; Ceylon and warmer parts of the world. 



The fruit is employed in native medicine. See Watt, Diet. Econ. Pi'od. I. c. 



28. SIEGESBECKIA, Linn. 



Herbs, usvially annual, more or less glandular-pubescent. Leaves 

 opposite, toothed. Heads small, in leafy lax panicles, heterogamous, 

 subradiate, yellow or white ; ray-flowers $ , fertile, 1-seriate ; disk- 

 flowers g , fertile or the inner sterile. Involucre campanulate or hemi- 

 spheric ; bracts few, herbaceous, glandular, the exterior (usually 5) 

 linear-cuoeate, spreading, the inner enclosing the ray-flowers. Efcep- 

 tacle small ; palese membranous, concave, often enclosing the flowers. 

 Corollas of § flowers with a short tube and 2-3-fid limb, those of the 

 5 flowers tubular, the limb campanulate and 5-fid, or narrow and 3-4- 



