DICOTYLEDONOUS PLANTS 231 



Heads numerous. Ray-flowers 10-15, neutral, yellow or yellow and 

 brown ; disk-flowers purple. Akenes hairy on the ribs ; pappus of 

 ovate, minutely toothed, awned scales. Common on river banks S.* 



VI. ANTHEMIS, L. 



Aromatic or ill-scented herbs. Leaves finely pinnately 

 divided. Heads many-flowered, with ray-flowers. Eays pis- 

 tillate or neutral. Involucre of many small, dry, close-pressed 

 scales. Akenes nearly cylindrical, generally ribbed; barely 

 crowned or naked at the summit. 



1. A. Cotula, DC. Mayweed, Dog-fennel. Leaves irregularly 

 cut into very many narrow segments. Heads small, produced all 

 summer. Disk yellow. Rays rather short, white, neutral. A low, 

 offensive-smelling annual weed, by roadsides and in barnyards. 



VII. ACHILLEA, L. 



Perennial ; leaves alternate, pinnately divided. Heads with 

 ray-flow^ers in a terminal corymb ; involucral bracts imbricated 

 in several series, the outer shorter ; receptacle chaffy. Ray- 

 flowers white or pink, pistillate and fertile ; disk-flowers per- 

 fect, tubular, 5-lobed. Akenes oblong, compressed, slightly 

 margined. Pappus none.* 



1. A. Millefolium, L. Yarrow. Stems often clustered, erect 

 from a creeping rootstock, simple, downy or wooUy, 1-2 ft. high. 

 Leaves lanceolate or oblong, the segments finely cut and divided, 

 smooth or downy, the lower petioled, the upper sessile. Heads 

 small, numerous, in flat-topped corymbs ; bracts downy. Ray-flowers 

 4-5, white or pink, rays 3-lobed at the apex. Common in old fields.* 



Vm. CHRYSANTHEMUM, Toum. 



Perennials, wdth toothed, pinnately cut or divided leaves. 

 Heads nearly as in the Anthemis, except that the ray -flowers 

 are pistillate. 



1. C. Leucanthemum, L. Oxeye Daisy, Whiteweed, Bull's- 

 eye, Sheriff Pink. Stem erect, unbranched or nearly so, 1-2 ft. 

 high; root-leaves oblong-spatulate, petioled, deeply and irregularly 

 toothed ; stem-leaves sessile and clasping, toothed and cut, the upper- 

 most ones shading off into bracts. Heads terminal and solitary. 



