408 . COMPOSITiE. Maruta. 



in few series, shorter than the disk. Receptacle conical, chaffy throughout 

 or only at the summit. Achenia obovoid or obpyramidal, ribbed, glabrous, 

 destitute of pappus. — Annual (European) fetid herbs; with tripinnately 

 divided leaves, and solitary heads terminating the branches. Rays white, 

 often deflexed ; the disk yellow. 



I. M. Cotula (DC. ! 1. c.) : scales of the involucre with whitish scarious 

 margins; receptacle conical, chaffy at the summit; the chaff subulate. — 

 Anlhemis Cotula, Linn, sj^ec. 2. p. 894 ; Engl. hot. t. 1772; Null. gen. 2. 

 p. 171 ; Bart. veg. mat. nied. t. 14 ; Hook. Ji. Bor.-Am. 2. p. 318 ; Dar- 

 lingt. Cest. p. 489. 



/3. rays few and small, or occasionally none. 



Roadsides, &c., throughout the United States, where it is completely 

 naturalized. /?. St. Louis, Missouri, i)r. £no'eZmann .' June-Nov. — Plant 

 hairy or nearly glabrous, with a strong unpleasant smell, and acrid proper- 

 ties. Achenia more or less tuberculate in lines. — May-weed. 



146. ANTHEMIS. Linn. (excl. spec.) ; DC. fi. Fr. Sf prodr. 6. p. 4. 



Heads many-flowered ; the rays pistillate. Scales of the involucre im- 

 bricated in few series. Receptacle convex or conical, with membranaceous 

 chaff among the flowers. Achenia terete or very obtusely quadrangular, 

 striate or smooth, destitute of pappus, or with a minute crown. — European or 

 Oriental odorous herbs, with 1-2-pinnately parted leaves ; the branches ter- 

 minated by single bractless heads. Rays usually white ; the disk yellow. 



1. A. arvensis (Linn.) : diffuse or erect, pubescent ; leaves pinnately 

 parted, the lobes linear-lanceolate, approximate, and with the teeth very 

 acute; the branches leafless at the summit, bearing solitary heads; scales 

 of the involucre with white scarious margins, obtuse ; chaff of the conical re- 

 ceptacle lanceolate, acuminate ; achenia crowned with a very short some- 

 what toothed margin. DC. I. c. — Engl. hot. t. 602 ,• Fl. Dan. t. 1179 ; 

 Darlingt.fl. Cest. jo. 488. 



Sparingly naturalized in the Northern States. June-Aug. — (T) The 

 Wild Cliammomile of Europe resembles Maruta Cotula, but is not fetid, with 

 larger heads, fertile rays, &c. 



A. nobilis, the officinal Chammomile, is said by Nuttall to be naturalized near Lew- 

 iston, Delaware. 



147. ACHILLEA. Linn. ; Schkuhr, liandb. t. 255 ; Less. S7jn. p. 250. 



Heads many-flowered ; the rays few, or 10-20, pistillate, short. Scales of 

 the involucre imbricated. Receptacle flat, or sometimes elongated, chaffy. 

 Achenia oblong, obcompressed, margined, destitute of pappus. — Perennial 

 herbs ; with alternate mostly pinnalifid or pinnately divided leaves, and small 

 corymbose heads. — Yarrow. 



§ 1. Involucre campanulate : rays {wliite) 5-20, flat, longer than the involucre 

 (in A. multiflora very short) : receptacle broad, nearly flat : achenia often 

 with wing-like margins. — Ptarmica, Tourn., DC. 



