AND GENERA OF PLANTS. 431 



gated; stem very short, pedicels naked, scapoid, one-flowered; outer sepals 

 rather shorter than the inner, somewhat smooth. 



Hab. The plains of Oregon. An annual, from four or five inches to a foot high. Stem scapoid, 

 hid among the leaves ; outer series of sepals slightly pubescent, the inner smooth, both linear-lan- 

 ceolate. Corolla pale yellow, externally purplish, very fugacious. Outer pubescent achenia 

 larger, purple, the inner straw-yellow, with smooth and shallower ribs. The whole plant nearly 

 resembles M. pterocarpus, for which it might readily be mistaken. 



*CRYPTOPLEURA. 



Capitulum many-flowered. Involucrum subcampanulate, imbricate in a few 

 series, the external shorter, pubescent and caliculiform. Receptacle naked. 

 Liguli elongated. Achenium smooth, linear-oblong, compressed, obtuse, 

 terminated by a very long filiform rostrum, the inner series bearing ten nar- 

 row, alated ribs; the outer series inflated, truncated at the apex, marked with 

 obsolete lines; basilar areola minute. Pappus very slender, white and sca- 

 brous. — Annuals, with the whole habit of the preceding genus. Stem sca- 

 poid, scarcely any; florets yellow, conspicuous, as in Troximon. — (The name 

 from x^vnifias, hidden, and rtPueupa, a rib, the ribs of the radial achenia being 

 obsolete or hidden.) 



Cryptopleura Californica. 



Hab. Near St Barbara, in Upper California. A dwarf annual, about three to four inches high; 

 hirsute and nearly scapoid. Leaves linear-lanceolate, incisely serrate. Involucrum in about three 

 series, the outer resembling a caliculum, with the divisions ovate and acute, hirsute ; the two inner 

 series nearly equal in length, lanceolate, almost smooth. Rays five-toothed, exserted. Pappus 

 softly pilose, white, very slender and scarcely hirsute; the stipe twice as long as the achenium; 

 all the achenia abrupt at the summit, straw white ; those of the exterior series truncated at the 

 summit and inflated, so that the seed is seen free in the testa: these are without striatures, and 

 almost without lines. The inner achenia are compressed, and have ten narrow sharply winged 

 ribs, 



*STYLOPAPPUS. 



Capitulum many-flowered. Involucrum hemispherical or subcampanulate, of 

 several series of nearly equal leaflets, calyculate; caliculum foliaceous, spread- 

 ing, of several series, mostly resembling the true leaves. Liguli elongated. 

 Branches of the stigma short, nearly smooth, and slenderly filiform. Re- 



