Dicotyledones. 121 



linear and erect. Achenes 4-5 -ribbed, prolonged into a beak bearing 

 a copious, soft, capillary pappus. Flowers yellow. 



i. Taraxacum officinale, Weber. (L., officina, workshop.) COMMON DAN- 

 DELION. Leaves pinnatifid or runcinate, clustered near the ground. Heads 

 crowded with many golden yellow flowers. Beak bearing the pappus becoming 

 very elongate and filiform in fruit. In pastures, fields, and yards. 



IX. PYRRHOPAPPUS. False Dandelion. 



(Gr., pyrrhos, reddish or flame-colored; pappos, pappus.) 



Mostly perennial herbs, with the general characteristics of the dan- 

 delion. Large heads of yellow flowers borne 'on long and usually 

 bracted peduncles. Pappus of a reddish color, surrounded at the base 

 by a soft, hairy ring, and borne above the achene on an elongate beak. 



1. Pyrrhopappus Carolinianus, DC. Stems branching, i to 2 feet high. Basal 

 leaves oblong or lanceolate, entire, toothed, or pinnatifid. Upper leaves nearly 

 lanceolate and partly clasping. .Outer bracts of the involucre awl-shaped and 

 spreading, inner bracts erect and indurated at the apex. Beak much longer than 

 the achene. In dry fields. 



2. Pyrrhopappus scaposus. (Gr., skapos, a staff.) ROUGH FALSE DANDELION. 

 Perennial from tuberous thickened roots. No stem leaves present. Basal leaves 

 deeply pinnatifid. Scape often naked, or with a small basal leaf. On prairies. 



X. SONCHUS. Sow Thistle. 



(The ancient Greek name.) 



Coarse annual or perennial herbs, exuding a milky secretion when 

 wounded. Leaves mostly lobed or pinnatifid, with prickly, toothed 

 margins. Heads of yellow flowers in corymbose or paniculate clusters. 

 Bracts of the involucre imbricated in several rows, becoming shorter 

 toward the outside. Achenes somewhat flattened, io-2o-ribbed. Pappus 

 of many soft and fine bristles, not borne on an elongated beak. 



1. Sonchus oleraceus, L. (L., oleraceus, pertaining to vegetables.) COMMON 

 Sow THISTLE or HARE'S LETTUCE. Annual, i to 5 feet high. Basal leaves 

 petioled, lyrate-pinnatifid in outline. Upper leaves sessile and clasping by an 

 auricled or sagittate base, margins with mucronate teeth. Achenes sfriate and 

 transversely wrinkled. Flowers pale yellow. In fields and waste places. 



2. Sonchus asper, Vill. (L., asper, rough.) SPINY-LEAVED Sow THISTLE. 

 Similar in general aspect to the preceding species. Lower leaves petioled, obovate, 

 or spatulate. Upper leaves sessile and clasping, with rounded basal lobes; the 

 margins more rigidly spiny-toothed than in the preceding species. Achenes 

 flattened and margined, 3-nerved on each side. In fields and waste places. 



