244 DICOTYLEDONS.— coMPOsiT.?^.. Achillea. 



35. PYRETHRUM. 

 Involucre hemisphaerical, imbricated with scales whose Inrders 

 are membranous. Receptacle naked. Pericarps crowned \\]i\i 

 a membranous viargin. 



1. P. Pflr//!e7z?//7W, leaves petiolate flat bipinnate, the segments 

 ovale cut, peduncles branched corymbose, stem erect, involu- 

 cre hemisphaerical pubescent, p. 246. — Waste places. 



2. P. inodorum, leaves sessile bipiiuiatifid with the segments ca- 

 pilla,-y, stem branched spreading, pappus entire, p. 246. — 

 Way -sides. 



3. P. maritimum, leaves bipinnatifid, the segments linear fleshy 

 awnless, stem diffuse branched^ pa])pus lobed. p. 246. — Sea- 

 coast. 



3G. MATRICARIA. 

 Involucre hemisphaerical or almost plane, imbricated with scales 



whose borders are membranous. Receptacle naked, almost 



cylindrical. Pappus none. 

 1. M. Chamoviilla, leaves glabrous bipinnatifid the segments 



capillary, involucre nearly plane its scales obtuse, p. 240. — 



Waste grounds. 



37. ANTHEMIS. 



7//yo/7/f/-e hemisphaerical ; its scales nearly equal, their margins 

 scariose. Receptacle convex, chaffy. Pericarps crowned with 

 a membranous border or pappus. 



1. A. iiobilis, leaves bipinnate, the segments linear subulate a 

 little downv, scales of the receptacle membranous scarcely 

 longer than the disk. p. 247. — Waste places. 



2. A. arvensis, leaves bipinnatifid, their segments linear lanceo- 

 late pubescent, receptacle conical, its scales lanceolate, pericarps 

 crowned with an entire pappus, p. 247. — Corn-Jields. 



3. A. Cotula^ leaves bipinnatifid glabrous, their segments subu- 

 late, receptacle conical, its scales setaceous, p. 247. — Waste 

 places. 



4. A. tinctoria, leaves bipinnatifid serrated downy beneath, stem 

 erect branched subcorymbose. p. 247. — Road-sides. 



38. ACHILLEA. 



Involucre ovate, imbricated, vmequal. Receptacle plane, chaffy. 

 Florets of the ray 5 — 10, roundish-obcordate. Pericarps 

 naked. 



* Flowers ichite, or rarebj reddish. 



1. A. Ptarmka, leaves linear lanceolate acuminate sharply ser- 

 rated, p. 248. — Pastures. 



2. A. Millefolium, leaves bipinnate slightly hairy, their segments 

 linear toothed acute, stems furrowed, p. 248. — [fay-sides. 



