Flora of the Palouse Region 191 



315. RUDBECKIA. 



Mostly perennial herbs: leaves alternate: heads mostly radiate, 

 many-flowered: ray-flowers sterile, rarely wanting; disk-flowers 

 perfect: receptacle elongated, becoming columnar : pappus a chaff- 

 like cup or 4 chaffy teeth more or less united into a cup: akenes 

 quadrangular and mostly laterally compressed. 



R. OCCidentalis Nutt. Perennial: stems erect, .5-1 m. tall, smooth: 

 leaves ovate, acuminate, coarsely dentate or nearly entire, short-petioled or 

 the upper entire, usually pubescent beneath, smooth above, 6-12 cm. long: 

 heads rayless, the disk at length ovate-conical or columnar, 3-5 cm. long, 

 dark-brown: involucre loose, foliaceous: akenes 3 mm. long: pappus merely 

 a low scarious rim on the apex of the akene. Moist open places, Thatuna 

 Hills. 



316. BALSAMORRHIZA. 



Low perennials: leaves mostly radical: heads large, usually sol- 

 itary: flowers yellow: receptacle flat or barely convex with linear- 

 lanceolate chaff: pappus none: ray-akenes obcompressed; disk- 

 akenes prismatic-quadrangular or laterally compressed. 



B. sagittata Nutt. Root stout and woody, resinous, the bark coarsely 

 ridged: basal leaves erect or nearly so, sagittate-hastate or oblong-cordate, 

 entire, silvery-canescent, 10-25 cm. long, on slender petioles about as long 

 or longer; cauline leaves few, small, spatulate or oblanceolate: peduncles 

 hardly exceeding the leaves, 30-50 cm. high: involucre white-woolly, 3-4 

 cm. broad: rays 10-25, yellow, entire and acute or rarely few-toothed at the 

 apex. Very plentiful. 



317. WYETHIA. 



Perennial herbs: stems simple, rarely branching: leaves alter- 

 nate, mostly entire and ample: heads many-flowered, solitary or 

 few, medium or large: flowers yellow; ray-flowers elongated: pap- 

 pus a chaffy crown or cup: ray-akenes neither obcompressed nor 

 laterally compressed. 



W. amplexicaulis Nutt. Whole plant dark-green and glabrous, more 

 or less resinous: radical leaves oblong-lanceolate or oblanceolate, entire or 

 somewhat dentate, acute or acuminate, erect or nearlv so, 15-40 cm. long, 

 narrowed at base into a short petiole; cauline shorter and relatively broader, 

 sessile and partly clasping at base: stems 30-60 cm. high, bearing a terminal 

 head and usually 1-5 smaller lateral ones, all peduncled: involucre 2-3 cm. 

 high; bracts lanceolate, acute, the outer ones longest, loose, somewhat 

 spreading: rays bright-yellow, about 3 cm. long: akenes clavate, 8-10 mm. 

 long, with a well developed crown, cut into small teeth and rarely bearing 

 1-2 awns. Abundant in wet meadows. This plant is one of the so-called 

 "compass-plants. ' ' 



