588 COMPOSITAE 



Body of the bur oblong, twice as long as thick or more. 

 Bur and its spines merely puberulent and glandu- 

 lar, very rarely somewhat hispid. 3. X. pennsylvanicum. 

 Bur and its spines very hispid. 4. X. commune. 

 Body of the bur oval or ovoid, not twice as long as 



thick. 5. X. echinatum. 



1. X. spinosum L. In waste grounds: Ont. to Fla., west to W. 



Va., Mo. and Tex. Naturalized from Europe or Asia. 

 Not uncommon as a weed in parts of our area. 



2. X. americanum Walt. (X. glabratum (DC.) Britton). In waste 



places: N. Eng. and N. Y. to Fla. and Mex., west to Neb. 

 Throughout most of our area, except in the pine-barrens, always 

 as a weed. 



3. X. pennsylvanicum Wallr. In waste ground: D. C. to Penn., 



Ont., and Minn. 



Known in our area only from Van Cortlandt, N. Y., and on waste 

 land in Northampton Co., Pa. 



4. X. commune Britton. In waste land: Que. to N. Y., Kan., 



Mo. and Ariz. 



Frequent throughout most of our area except in the pine- 

 barrens. 



5. X. echinatum Murr. Sea, lake and river beaches: Vt. and 



N. N. Y. to Minn, and N. Car. 



Common on sandy shores along the coast, throughout our area. 



X. speciosum Kearney has been collected in Westchester Co. and on L. I., not 

 certainly established. 



COMPOSITAE 



Stigmatic lines at the base of the stigma or below the middle. 



Stigmas filiform or subulate, hispidulous. Tribe i. Vernonieae. 



(Genera 1 and 2. See page 589.) 

 Stigmas more or less clavate, papillose-puberulent. Tribe 2. Eupatorieae. 



(Genera 3-7. See page 590.) 

 Stigmatic lines extending to the tip of the stigma or to the 

 appendages. 

 Anthers without elongated appendages at the top. 



Anther-sacs tailed at the base. Tribe 4. Inuleae. 



(Genera 21-26. See page 617.) 

 Anther-sacs not tailed at the base. 

 Recptacle naked. 



Bracts of the involucre well imbricated. 



