COMPOSITAE (COMPOSITE FAMILY) 



829 



985. X. spinosum. 



1. X. SPIN6SUM L. Hoary-pubescent, armed at the axils 

 with triple spines ; stems slender ; leaves lanceolate or ovate- 

 lanceolate, short-petiolate, white-downy 

 beneath, often 2-3-lobed or -cut ; fruit 

 about 1 cm. long, with a single short beak 

 or beakless. Waste places, Me. to Ont., 

 westw. and southw. (Nat. from Trop. 



9S6. X. canadense. 



2. X. canadense Mill. Leaves broadly ovate, cordate, 

 usually 3-lobed and simply or doubly dentate ; burs gla- 

 brous or merely granular- or glandular-puberulent ; the 

 body fusiform-ellipsoid, 14-17 mm. long, 5-8 mm. in 



diameter ; the beaks usually 2, straight 



r S or but slightly curved ; prickles scat- 



^\f^W/ tered, straight-tipped or hooked. (JT. 



\$KW&/ pensylvanicum Wallr. ? ; X. pungens 

 vS^lP'^iS^ Wallr. ; X. (jlabratum Britton.) Rich 

 soil, especially in moist places. FIG. 

 986. 



3. X. commune Britton. Similar in habit and foliage ; 

 beaks of the bur more or less strongly incurved, usually 

 hooked at the summit ; prickles numerous, crowded, 3-6 mm. 

 long, hooked at the summit, hairy as is the body. Similar 

 situations. FIG. 987. 



"<%.Kii:^ 4 - X. specibsum Kearney. 



Of the same habit, foliage, 



987. X. commune. etc. ; bur with numerous 



long (8-10 mm.) filiform 



usually stramineous and very hairy prickles; 



beaks moderately incurved and hooked. Waste 



places and low moist ground, Tenn. to N. Dak. 



and Tex.; also sparingly adventive on wool- 



waste, etc., eastw. FIG. 988. 



5. X. infle"xum Mackenzie & Bush. Habit, 

 foliage, etc., as in the three preceding species ; 

 bur large, the body 2 cm. long, 6-7 mm. thick, 

 ovoid-fusiform, merely granular-pub erulent ; 



beaks 2, very strongly 



/r~ incurved, often forming 



L j, a loop or arch over the 



C^ffr ' fruit ; prickles numerous 



VJRpHLv / b ut less crowded than in 

 the preceding, firm in 

 texture, brownish, arcu- 



ate, hooked at the summit, granular-puberulent, at least 

 toward the base. Bottom lands, Courtney, Mo. (Bush} . 



6. X. echin^tum Murr. Of the same habit, etc.; burs 

 plumper; the body thickish-ovoid, 15-22 mm. long, 8-12 

 mm. thick, for the most part densely pubescent as are also 

 the numerous short rigid hooked prickles and stout falcate- 

 incurved beaks. ( X. canadense, var. Gray.) Sea- 

 beaches, lake-shores, etc., Me. to N. C., and westw. chiefly 

 x. echinatum. along the Great Lakes to N. Dak. and Sask. FIG. 989. 



43. HELI6PSIS Pers. OX-EYE 



Heads many-flowered ; rays 10 or more, fertile. Involucral bracts in 2 or 3 

 rows, nearly equal ; the outer leaf-like and somewhat spreading, the inner shorter 

 than the disk. Receptacle conical; chaff linear. Achenes" smooth, thick, 4- 



988. X. speciosuna. 



