214 COMPOSITES. 



9. S. MIKANIOIDES, Otto. Glabrous, twining and trailing to the 

 height of 20 feet: leaves roundish-cordate-hastate, sharply 5 7-angled, 

 2 5 in. long, nearly as broad, on petioles as long or longer, these with 

 a reniform stipulaceous lobe on either side at base: heads small, in com- 

 pound corymbs terminating axillary branchlets: rays none: disk-fl. 9 

 15. Plentiful along banks of streams at the base of the Oakland and 

 Berkeley Hills. Native of S. Africa; flowering profusely in January. 



Suborder 10. CYNAROCEPHAL^E. 



Herbs with watery juice, usually prickly leaves, and flowers in dense 

 ovoid or globose heads; involucre imbricate. Receptacle densely setose. 

 Flowers all alike and perfect, or the marginal larger than the others and 

 neutral. Corollas regular or slightly irregular, deeply cleft into 5 long 

 and narrow lobes; the marginal in some enlarged and palmatifid but 

 never ligulate. Stamens syngenesious and also rarely monadelphous 

 below. Anthers caudate. Style slightly or not at all cleft, commonly 

 with a pubescent node or ring below the stigmatic part. Achenes thick, 

 hard, smooth, basally or obliquely inserted. Pappus setose, plumose, or 

 rarely paleaceous, sometimes wanting. 



Pappus of many setose bristles CENTAUEEA 68 



' ' double, i. 6. of 2 different sets j of bristle8 CNICUS 69 



<of paleae CENTROPHYLLYTTM 70 



" many series of barbellate paleae SILYBUM 71 



" united at base, deciduous in a ring; 



in many series of plumose bristles CTNARA 72 



in one series of plumose bristles CARDOTJS 73 



68. CENTATJREA, Linn. Annual or biennial herbs of various habit. 

 Leaves unarmed and decurrent, or spinescent and merely sessile. Heads 

 ovate; the imbricated bracts various. Achenes compressed or some- 

 what tetragonal, the insertion somewhat oblique or sublatral. Pappus 

 of many slender scabrous bristles, mostly in two sets, or occasionally 

 wanting. All our species naturalized from Europe. 



* Bracts of involucre armed with a rigid spine; marginal corollas 

 not enlarged. ' 



1. C. CALCITRAPA, L. Stoutish, rigid, 1 2 ft. high, very widely 

 branching, leaves narrow, laciniate-pinnatind; the uppermost somewhat 

 involucrate-crowded about the sessile head: principal bracts of the 

 involucre armed with a widely spreading long and rigid subulate spine, 

 which bears 2 or 3 spinules on each side at base: corollas red-purple: 

 pappus none. Common along roadsides at and near Vacaville. 



2. C. SOLSTITIALIS, L. Erect, 1 2 ft. high, canescent with cottony 

 wool: radical leaves lyrate-pinnatifid; cauline lanceolate and linear, 

 mostly entire, decurrent on the branches in narrow wings: heads pedun- 

 culate: middle bracts of the in volucre with a long rigid spreading spine 



