A. ABSINTHIUM. 



107 



toothed; disk-flowers 30 to 50, fertile, corolla campanulate, about 1.5 to 2 mm. long, 

 5-toothed, glabrous; style-branches spreading, those of the disk-flowers truncate and 

 penicillate at the ends; achenes nearly cylindric, but narrowed at base and shghtly 

 rounded to the summit, smooth, glabrous. 



Native of Europe, thoroughly established as an introduced wayside plant in eastern 

 Canada and northern New England; less common from North Carolina to Utah, eastern 

 Washington (where spreading rapidly), central Oregon, and British Columbia. Type 

 locality, Europe. Collections: Near Topsail, Conception Bay, Newfoundland, Howe 



! rupesfr/s \ 

 \ (Siberian) I 



Glabrous. 

 Old World 



I ip.pa/fcrsonA 



Heads i-s, 

 5-7 mm. broad; 

 disk-fls. jo-120 



Herbaceous; heads 

 racemose or solitary 

 Ivs. silvery. American 



FiQ. 14. — Phylogenetic chart of the species of Artemiiia section AfcsirUAtum. 



and Lang 121 Ji. (Gr, NY); Brome, Quebec, Pmse 1311 (Gr); Plevna, Ontario, August 14, 

 1^02, Fowler (Gr); Veazie, Maine, July 31, 1891, Fernald (Gr); Milford, Connecticut, 

 Williams 5539 (Gr); Morristown, New York, Phelps 1767 (Gr); Brookings, South 

 Dakota, September, 1893, Thornber (UC); Yellow Bay, Montana, Butler 470 (NY); 

 Medicine Hat, Assiniboia, Macoun 10980 (Gr) ; Salem, Oregon, J. C. Nelson 2395 (Gr, 

 US). 



RELATIONSHIPS. 

 This differs from the native members of its section in the much more robust habit 

 and ample foliage. It is never decidedly woody at the base, as is usually true of A. 

 frigida, and the profuse leafy panicle at once distinguishes it from A. scopulorum. 

 However, in technical characters it is very close to both of these, thus lending support 

 to the view that the section Absinthium is a natural group, even though its members 

 are few and widely separated geographically. Outside of the members of its own section, 

 it is most nearly like the native A. franserioides, of the southern Rocky Mountains. 



