COMPOSITES (composite FAMILY.) 497 



SuBTRiBE II. CHRYSANTHEMKiE. Eeceptacle not chaffy. 



36. CHRYSANTHEMUM. Eays yellow. Leaves undivided or pinnatipartite. Mar- 



ginal akenes triquetrous or 3-vvinged. Disk-akenes top-shaped. 



37. PYKETHRUM. 2j! ^ Kays white or yellow or 0. Leaves pectinate or dissected. 



Akenes prismatic or turbinate, ribbed, crowned. 



38. MATRICARIA. Heads discoid or white-rayed. Leaves dissected. Akenes teretish, 



3-5-ribbed at inner face, bald, or crowned. Fragrant herbs. 



39. BROCCHIA. Greyish, desert herbs, with pinnatifid leaves and small, discoid heads 



resembling those of Cotula. 



40. ARTEMISIA. ^ Heads discoid, panicied. Leaves dissected, rarely simple. Akenes 



obovate, bald. 



Tribe VII. SENECIONIBJE. Heads heterogamous, rarely homogamous. Scales 

 of involucre commonly 1-2-rowed, usually with a lew accessory scales at base. Eeceptacle 

 generally naked. Anthers-short-sagittate at base, not caudate. Branches of style truncate 

 or appendaged at tip, or filiform-club-shaped. Pappus bristly, hairy, or 0. 



* Branches of style flattened or filiform-club-shaped. Rays yellovj. 



41. TUSSILAGO. 2f Stems 1-headed, scape-like, leaves cordate-orbicular. 



* * Branches of style truncate, pennicillate or appendaged. Rays yellow. 



42. DOROjSTICUM. 2f Scales of involucre in 2-3 rows. Marginal akenes bald. 



43. SENECIO. (D If Scales of involucre in 1 row. All the akenes pappose. 



Tribe VIII. €AIiENDUl.A€EilE. Heads commonly radiate, the marginal flower- 

 ets pistillate, the disk flowerets sterile. Anthers sagittate at base. Style of the pistiHute 

 flowers with truncate branches, of the sterile undivided. Akenes large, bald (in JDipteroeome 

 with a pappus of few bristles). Receptacle naked. 



44. CALENDULA. (D 2X Rays yellow or orange. Leaves undivided. Akenes curved, 



beaked, often inflated. 



45. DIPTEROCOME. Low, desert herbs resembling Koelpinia, with minute, sessile, dis- 



coid heads, and echinate akenes ending in two horns. 



46. TRIPTERIS. ^ Low, desert shrubs, with small heads, yellow rays, and 3-winged 



akenes. 



Tribe IX. GUNI>EIiIE^E. Headlets several-flowered, aggregated into a large, 

 globular, compound head. Scales of involucre and bracts prickly, closely united. Anthers 

 sagittate. Branches of style rough, somewhat flattened. Pappus cup-like. 



47. GUNDELIA. Headlets 5-7-flowered, the central floweret fertile. 



Tribe X. CYNAREiE, Heads homogamous, flowers tubular, perfect, rarely 

 heterogamous, with marginal flowers 2-lipped or strap-shaped, neutral or sometimes pistil- 

 late. Receptacle usually densely bristly or chafly. Anthers sagittate at base. Style thick- 

 ened under the short, usually erect branches, or surrounded by a ring of hairs. 



Subtribe I. E€mNOPSII>.aE, Headlets 1-flowered, crowded into dense, globular 

 or hemispherical heads. 



48. ECHINOPS. 2|! Compound heads spherical, densely spiny. Leaves pinnatisect, spiny. 



49. ACANTHOLEPIS. Desert herbs. Compound heads hemispherical, with spinescent 



involucre. Leaves linear-lanceolate, weak-prickly. 



Subtribe II. CARLiINEiE, Heads several-oo -flowered. Akenes silky or downy. 

 Pappus chaffy, chaff sometimes finely cleft. 



50. CARDOPATIUM. If Very spiny, low herbs, with numerous, subsessile, spiny heads, 



in terminal, corymbose cymes. Flowerets blue. 



51. XERANTHEMUM. Unarmed herbs, with entire leaves, and scarious involucre, the 



inner scales radiating, pink or pallid. 



66 



