364 COMPOSITE. Matricariu. 



cet. 31. Arctic sea-coast to Alaska and the Hudson Bay country, commonly in a dwarf and 

 monocephalous form with blackish involucre (var. nana, Torr. & Gray, 1. c., Chrysanthemum 

 grandiflorum, Hook., Pyrethrum inodorum, var. nanum, Hook. Fl. 1. c.), occasionally wanting 

 the ray, vnr. eligulata, Seem. Bot. Herald, 33. The common taller and branching European 

 form is naturalized in some parts of Canada and Maine. (Eu., Asia.) 



2. Akenes more terete, with 3 to 5 slender often unequal or indistinct ribs, 

 the surface commonly developing mucilage when wetted. 



M. CHAMOMILLA, L. Annual, a foot or two high, quite resembling Anthemis Cotula, aromatic : 

 heads 3 lines high, and rays of the same length : bracts of the involucre oblong, fuscous : 

 receptacle ovate-conical or oblong in age : akenes small, with an obscure border and usually 

 no distinct pappus; the inner face unequally 5-ribbed. Curt. Fl. Lond. v. t. 63; Schk. 

 Ilandb. t. 253. Waste grounds, S. New York and New Jersey. (Nat. from Eu. ) 



Var. CORONATA, GAY, ex Boiss. Akeues of the ray and commonly most of the disk 

 furnished with a conspicuous thin-scarious cleft and toothed and sometimes unilateral pap- 

 pus, not rarely surpassing the tube of the corolla. M. coronata, Gay in Koch, Fl. Germ, 

 ed. 2, 416. M. Courrantia, DC. 1. c. 72; Webb, Phyt. Cauar. ii. t. 89. M. pyrethroides, DC. 

 1. c., from Mex. Courrantia chamomHloides, Schultz Bip. in Webb, Phyt. Canar. ii. 278. 

 Cult, fields, S. Texas, Bigelow. (Adj. Mex.) 



M. dlscoidea, DC. Annual, somewhat aromatic, glabrous, a span to a foot high, very 

 leafy : leaves 2-3-piunately dissected into short and narrow linear lobes : heads all short- 

 peduucled : bracts of the involucre broadly oval, white-scarious with greenish centre, hardly 

 half the length of the well-developed greenish yellow ovoid disk : receptacle high-conical : 

 akenes oblong, somewhat angled, with an obscure corouiform margin at summit, this occa- 

 sionally produced into one or two conspicuous oblique auricles of coriaceous texture. Prodr. 

 vi. 50; Torr. & Gray, Fl. ii. 413. M. tanacetoides, Fisch. & Meyer, Ind. Sem, Petrop. vii. 52. 

 Santolina suaveolens, Pursh, Fl. ii. 520. Artemisia matricarioides, Less, in Linn. vi. 210. 

 Tanacetum matricarioides, Less. Syn. 265. T. suaveolens, Hook. Fl. i. 327, t. 110. T. puuc.i- 

 florum, DC. 1. c. 131, not Richards. Cotula matrirarioidcs, Bong. Veg. Sitch. 150. Lepi- 

 dotheca (Lepida?ithus) suaveolens, Nutt. Trans. Am. Phil. Soc. n. ser. vii. 397. Open ground, 

 W. California to Unalaska and Behring Island, east to Montana, and becoming naturalized 

 in the Atlantic States near railroad stations. (N. Asia; nat. in N. Eu.) 



174. CHRYSANTHEMUM, Tourn., L. (Old Greek name, Xpvo-ai- 

 OC/JLOV, i. e. golden flower.) Chrysanthemum & Leucanthemum, Tourn. Pyre- 

 thrum, Gaertu., &c. --Mostly an Old- World genus, only a small portion of the 

 species with yellow rays : n. summer. 



C. SEGETUM, L. (CORN-CHRYSANTHEMUM or CORN-MARYGOLU of Europe), is a ballast-weed 

 at New York and Philadelphia, and is in fields at Oakland, California. This and C. CORO 

 NARIUM, L., are genuine Chrysanthemums, annuals, with golden yellow rays as well as disk- 

 flowers, and 3-sided or 3-winged ray-akeues. 



C. SINENSE and C. INDICUM, L., of China and Japan, are the parents of the autumn-flowering 

 perennial Chrysanthemums of gardens and houses, and form a peculiar section of the genus. 



C. ? NANUM, Hook. Fl. i. 320, is Blcnnosperrna Call for nicuin. 



1. PYRETHRUM, Benth. & Hook. Herbaceous or suffruticulose perennials; 

 with comparatively large and broad heads, either solitary or loosely corymbose : 

 rays usually conspicuous: akenes all equably 5-10-costate. Pyrethrum, Ga?rtn. 

 Pyrethrum, Leucanthemum, Plagius, &c., DC. Tanacetum in part, Schultz Bip. 



# Rays described as yellow, but perhaps white, short : leaves bipinnately dissected into many small 

 linear lobes. 



C. bipinnatum, L. Slender, a span to a foot high from a creeping rootstock, villous or 

 glabrate, bearing usually a solitary head of half-inch diameter : rays obovate, little sur- 

 passing the merely convex disk : pappus a short crown. Spec. ii. 890 ; founded on Gmel. 

 Fl. Sibir. ii. 205, t. 85, f. 1. Pyrethrum bipinnatum, Willd. Spec. iii. 2160; DC. Prodr. vi. 60. 

 Tanacetum Kotzebuense, Bess., ex DC. 1. c. 131. T. bipinnatum, Schultz Bip. Tauacet. 48. 



