COMPOSITAE (COMPOSITE FAMILY) 



829 



9SC. X. canadense. 



1. X. SPINOSUM 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. 

 985. X. splnosum. Am ^ F , G 985 



2. X. canad6nse Mill. Leaves broadly ovate, cordate, 

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

 brous or merely granular- or glaiidular-puberulent ; the 

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



diameter ; the beaks usually 2, straight 



or but slightly curved ; prickles scat- 

 tered, straight-tipped or hooked. (X. 



pensylvanicum Wallr.-? ; X. pungens 



Wallr. ; X. glabratum 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 summjt, hairy as is the body. Similar 

 situations. FIG. 987. 



4. X. specibsum Kearney, 

 the same habit, foliage, 



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-puberulent ; 



beaks 2, very strongly 



incurved, often forming 



a loop or arch over the 



fruit ; prickles numerous 



but less crowded than in 



the preceding, firm in 



texture, brownish, arcu- 



9S7. X. commune. 



988. X. speciosum. 



9s'.). X. echinatuin. 



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

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



6. X. echinatum 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 

 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 

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

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



