188 CAMPAXULALES 



7. Boebera. 1012. 



1. Boebera papposa (Vent.) Rydb. Fetid Marigold. 

 Common all over the state. Brock; Franklin; Grand Rapids; Lin- 

 coln; Minden; Nebraska City; Plain view; Red Cloud; Scotts Bluff 

 County; "Valentine; Wymore. 



8. Pectls. 1012. 



1. Pectls angustifolia Torr. 



In dry soil in the western part of the state. Deuel County; Ft. 



Niobrara. 



Tribe 8. ANTHEMIDEAE. 



Rays usually present, white or pink; receptacle chaffy. 



Achenes flattened, heads small. 1. Achillea. 



Achenes terete, heads larpe 25 cm. or more broad. 2. Anthem is. 

 Rays wanting or rudimentary, receptacle not chaffy. 



Heads corymbed, pappus a short crown. Tanacetum. 



Heads racemose, spicate or panicled, pappus none. 4. Artemisia. 



1. Achillea. 1013. 



1. Achillea millifolium L. Yarrow, Milfoil. 



A common weed in the eastern part of the state. Fairbury; Hat 

 Creek Basin; Lincoln; Nebraska City; Ponca; Red Cloud. 



2. Anthemis. 1014. 



1. Anthemis cotula L. Fetid camomile. 



Common in waste places in the eastern part of the state. Brown 

 Ccunty; Lincoln; Nebraska City; St. Paul. 



4. Artemisia. 1017. 



Marginal flowers pistillate, central flowers perfect, mostly herbs. 

 Central flowers sterile, not producing seeds, mostly with entire 

 styles. 

 Herbs, sometimes woody at the base, heads 2-4 mm. broad. 

 Leaves pinnately dissected into narrow linear lobes. 



Heads 2 mm. broad, in a broad panicle. 1. A. caudata. 



Heads 4 mm. broad, in a narrow panicle. 2. A. canadensis. 

 Leaves linear, mostly entire, sometimes 3-cleft or the lower 

 more divided. 

 Leaves glabrous. 3. A. dracunculoides. 



Leaves finely and densely pubescent. 4. A. glauca. 



Shrubs, heads small, numerous, about 1 mm. broad. 5. A. filfolia. 

 Central flowers fertile, producing seeds, their styles 2-cleft. 

 Receptacle with long woolly hairs. 



Plants 2-3 dm, high, leaf segments linear-filiform, less than 1 



mm, wide. 6. A. frigida. 



Plants 6-12 dm, high, leaf segments oblong or linear-oblong, 



over 1 mm. broad, 7. A. absinthium. 



Receptacle glabrous, or slightly pubescent. 



