ASTERACEAE. 377 



disposed clusters of broad heads; leaves lanceolate, glabrate above, 

 glandular and balsamic-scented, strongly adnate-decurrent; heads 

 5-7 mm. high, nearly as broad, white or yellowish; outer bracts 

 ovate or oblong, the inner acute. 



Rather common on the dry plains and foothills. April-July. 



3. G. bicolor Bioletti. Perennial from a lignescent root; stems 

 several, 4-6 dm. high, strict, mostly simple, very leafy; herbage 

 white with close wool except the under sides of the leaves, these deep 

 green and slightly glandular; stem-leaves narrowly linear, attenuate, 

 acute, erect, short-decurrent at the narrow base, viscid-glandular 

 above; heads in a small close cyme; involucre broadly campanulate, 

 much imbricated, pearly white; bracts ovate and oblong, obtuse. 



Occasional in dry washes. Santa Anita Wash, near Monrovia. 



4. G. chilense Spreng. Stems rather stout, from an annual or 

 biennial root, 3-6 dm. high, loosely fioccose or the upper faces of the 

 leaves often nearly glabrous; leaves lanceolate or the lower often 

 spatulate or oblanceolate; heads in close clusters at the ends of the 

 corymbose branches; involucre hemispheric, with a yellowish-green 

 tinge; bracts oval or oblong, obtuse. 



Common along the seashore on the sand-dunes and frequent in 

 our foothills and mountains, extending into the pine belt. 



5. G. microcephalum Nutt. Biennial; stems slender with several 

 erect branches, 5-8 dm. high, loosely corymbose-paniculate above, 

 the whole herbage white with a persistent wool, not at all glandular 

 or heavy-scented; leaves linear or the lower spatulate, slenderly 

 decurrent; heads rather few or loose in the paniculately or cymosely 

 disposed clusters; involucres ovate; bracts white, ovate or oblong, 

 obtuse, except the inner. 



' Frequent in dry washes and in the chaparral belt. June-Sep- 

 tember. 



6. G. palustre Nutt. Low, branching annual, 5-15 cm. high, 

 fioccose with long wool; leaves spatulate to oblong and lanceolate; 

 heads glomerate, leaf y-bracted ; involucres about 2 mm. high, 

 embedded in loose wool; bracts linear, obtuse, brownish-green, the 

 tips white. 



Occasional along river bottoms and on the margins of ponds. 

 May-October. 



5. G. purpureum L. Biennial, simple or branching, erect or 

 decumbent at the base, 2-3 dm. high, canescent with a dense close 

 wool; leaves spatulate, obtuse, usually becoming glabrate and 

 green above; heads crowded in an elongated more or less interrupted 

 spiciform inflorescence; involucre brownish; achenes sparsely sca- 

 brous. 



Lincoln Park, Davidson. 



Tribe 4. AMBROSIAE. Ragweed Tribe. 

 Herbs with mostly alternate leaves and greenish or 

 white unisexual flowers. Staminate heads racemose or 



