im 



COMI'OSITAE. 



Tribe 6. Madieae. Tabweed Tribe. 

 45. MADIA Mol. Tabweed. 

 Glandular- viscid heavy-scented erect annual or perennial herbs. Leaves, 

 at least the upper, alternate, entire or serrate. I leads axillary and terminal. 

 Flowers yellow, opening in the evening and closing before noon of the next 

 day. [nvolucre angled by the salient carinate or almost conduplicate bracts; 

 bracts in 1 series, completely enfolding the laterally compressed ray-achenes, 

 and with tree moderately long or short tips. Receptacle Hat or convex, bearing 

 a single row of chaffy bracts between ray- and disk-flowers and often united 

 and forming a cup. Disk-corollas in ours pubescent. Eays few to many, 

 3-lobed. Bracts of involucre deciduous with the mature ray-achenes, these beak- 

 less (except in no. 5). Disk-achenes fertile or abortive. (Madi, the Chilian 

 name.) 



A. Receptacle glabrous; annuals except no. 4. 

 Achenes beakless. 



Rays very short and inconspicuous; achenes of ray curved; pappus none. 

 Plants stoutish and viscid-glandular; heads in clusters. 



Herbage ill-scented 1. M. saliva. 



Herbage honey-scented 2. M. capitata. 



Plants slender and moderately glandular; heads scattered 3. ill. dissititiora. 



Rays showy; achenes of ray incurved; leaves some or mostly opposite; pappus present... 



4. M. inactivities. 



Achenes with a minute reflexed beak; rays Yi in. long; pappus none 5. M. radiata. 



B. Receptacle Ulimbrillate-hirsiitc ; annuals. 



Achenes beakless, those of the ray not incurved; pappus none; rays showy 



6. M. elegans. 



1. M. sativa Molina. Chile Tarweed. Eobust, 1 to 4 ft. high, pubescent 

 with slender hairs and beset with pedicellate very viscid glands, ill-scented; 

 leaves from broadly lanceolate to linear; heads 5 to 6 lines high, short-peduncled 

 or sessile, disposed in the upper axils and at the ends of short branches; 

 bracts of involucre hispid; rays 5 to 12, with pale yellow ligules about 2 lines 

 long; cup of receptacle campanulate and enclosing many disk-achenes, these 

 cuneate-oblong and 4-angled, prominently 1-nerved on the sides and 2 lines long; 

 ray-achenes somewhat falcate-obovate, either with or without an obvious nerve 

 on the sides. 



Common in vacant lots, waysides, etc., about San Francisco Bay. Doubtless 

 naturalized from Chile. July-Aug. 



2. M. capitata Nutt. Nuttall Tarweed. Erect, iy 2 to 2% ft. high, 

 simple or branching; herbage very viscid-glandular, honey-scented; leaves 

 linear; heads somewhat longer than in the preceding, capitate-congested at the 

 ends of the branches; bracts of involucre short -bristly; cup of receptacle nar- 

 row and nearly closed, containing very few to many achenes; bracts of in- 

 volucre and achenes semi-persistent. 



North Coast Kanges; South Coast Ranges (Gilroy, Santa Cruz). 



3. M. dissitiflora (Nutt.) T. & G. Gum-weed. Very slender, 1 to 2 ft. 

 high, simple or loosely branching, moderately or scarcely at all viscid, at least 

 below; flowers sulphur-yellow; heads 3 (or barely 4) lines high, scattered or 

 loosely paniculate; cup of receptacle ovoid but not closed, containing few disk- 

 flowers; rays 5 to 8, 1% to 2 lines Long; aehenes short and broad (1 to 2 linos 

 Long). 



Stream banks, open bushy places or wooded slopes in the mountains: North 

 Coasl Ranges to the Santa CniS Mts. (where very slender forms pass into 



coarser tonus, as much as ."»'._, ft. high, by every gradation), and Southern 



( ali I'oinia. 



