Matricaria. ' COMPOSIT.E. 401 



none or a short chaffy crown. — Herbs, of numerous species in the Old World, a 

 very few have become roadside weeds in the United States. The only common 

 one is the May-weed, which has reached California, viz., 



1. A. Cotula, Linn. A much branched, somewhat pubescent, strong-scented 

 and acrid annual, a foot or less high : the alternate leaves thrice pinnately divided 

 into small linear-subulate lobes : heads rather small terminating the branches, 

 somewhat corymbose : rays soon reflexed, white, sterile, having an imperfect style 

 or none : disk-flowers yellow : receptacle conical, naked toward the margin, but 

 with almost bristle-shaped chaff near the centre : pappus none. — Maruta Cotula, 

 Cass. : differing from true Anthemis in the sterile rays, &c. 

 Sparingly found along roadsides : introduced, but not yet common. 



91. CHRYSANTHEMUM, Linn. 



Head many-flowered, with numerous pistillate rays ; the disk-flowers usually all 



fertile. Involucre hemispherical or flatter ; the more or less scarious short and 



appressed scales imbricated in several series. Eeceptacle flat or convex, naked. 



Kays usually elongated : disk-corollas often flattened (obcompressed) or 2-winged 



below, 4 - 5-toothed. Akenes short, nearly terete, several-ribbed or angled, truu- 



cate :it tin- tip. mostly (in ours) destitute of pappus. 



\ large and diversified genus in the old World (especially when it includes Leucanthemum and 

 Pifrethrum i, but not indigenous t" North America except in the arctic regions. Only one species 

 is much naturalized in the United States, viz. 



1. C. Leucanthemum, Linn. A perennial weed, spreading from short run- 

 ning rootstocks, nearly glabrous, a foot or two high: stems simple or sparingly 

 branched, the naked summit bearing a large head : leaves incisely pinnatifid or 

 toothed ; the lower spatulate ; the upper becoming linear and smaller : scales of the 

 involucre with somewhat rusty tips: rays white (over half an inch long): disk 

 yellow : akenes many-ribbed. — Leucanthemum vulgare, Lain. 



In fields at Santa Cruz ; probably in some other places : introduced from the Old World. Not 

 yet, perhaps may not become, in California the troublesomi weed that it is in the Atlantic S 

 where it takes possession of meadows, and is known as Ox-eye Jjni.ii/, While Daisy, and IVhiU- 

 weed. 



92. MATRICARIA, Linn. 



Eead many-flowered, with or without rays. Involucre hemispherical or flatter, 

 of numerous and more or less scarious appressed scales in low series. Eeceptacle 

 conical or ovate, naked. Corollas, akenes, &c, as in the preceding genus. Pappus 

 Done or a minute crown. — A rather large genus of the Old World ; only the fol- 

 lowing "ii tin- Pacific coast, where it is apparently indigenous. 



I. M. discoidea, DC. Annual, a span or two high, branching, glabrous, 



leafj : Leaves twic 'thrice pinnately dissected into numerous short and narrow 



linear divisions: heads small. Bhort-peduncled : involucre of broadly oval scabs 

 with white-scarious margins: rays none: disk greenish-yellow, much elevated: 



I icle high i Leal : akenes with an obscure eoroitifomi margin in place of pap- 



pus. - M. tanacetoides, Fischer & Meyer. Santolina suaveolens, Pursh. Tanacetum 

 riUUricarurides, Less. T. suaveolens, Hook. T. pauciflorum, l'('. Artemisia matri- 

 carioides, Less. Cotula matricarioid.es, Bongard. Lepidotheca (in errata) or Ltpi- 

 danthus suaveolens, Nuti. iu Trans. Amer. Phil. Soc. 



\\ ite grounds, through tic whole length of the State, and north to Unalaska. 1 



migrated to and beyond the Mississippi as a weed, as also to some places in the north of Europe. 



Said o. In- use, 1 in California as ;i domestic remedy for agues and bowel-complaints. II' 

 quarter of an in. b, .a- in fruit half on inch in length, greenish-yellow. 



