228 COMPOSITE FAMILY. 



35. HELIOPSIS. Rays 10 or more, pistillate. Scales of the involucre in 2 or 3 rows, the 



inner shorter than the disk. Beceptacle conical. Akenes 4-angled, somewhat cubi- 

 cal ; no pappus. Leaves opposite, petioled, triple-ribbed. 



36. ECHINACEA. Kays numerous, rather persistent, long, drooping, pistillate but sterile, 



rose-purple. Scales of the involucre narrow aDd spreading. Receptacle conical ; 

 the persistent and rigid spiny-tipped chaff longer than the purplish disk corollas. 

 Akenes thick and short, 4-sided, and with a toothed border for a pappus. Leaves 

 chiefly alternate, 8-5-ribbed. 

 ST. RUDBECKIA. Rays several or numerous, neutral. Yellow scales of the involucre 

 in about 2 rows, spreading. Receptacle conical or columnar. Chaff soft. AkeneB 

 short, 4-anguIar, marginless, flat at the top ; pappus none or a short even cup or 

 border. Leaves alternate. 



Series II. Head with all the flowers strap-shaped and per- 

 fect. Juice milky. Leaves alternate. 



* No pappus. 



69. LAMPSANA. Heads small, 8-12-flowered, loosely panicled. Involucre cylindrical, 



with 8 scales in a single row. Akene oblong. Flowers yellow. 



* * Pappus of both chaff and bristles, or of chaffy scales alone which form a crown or 



cup on top of the akene. 



70. KRIGIA. Heads medium to large, terminating naked scapes or branches, yellow. 



Scales of the involucre in two more or less defined rows. Akene short and truncate, 

 top-shaped or column-like, terete or angled. Pappus double, the outer row of thin 

 chaffy scales, the inner of slender bristles. Leaves mostly radical. 

 Tl. CICHORIUM. Head of several blue flowers. Involucre double ; the outer of 5 short 

 and spreading, the inner of about 10 erect scales. Akenes short, with broad sum- 

 mit. Pappus of small chaffy scales. Stems twiggy, leafy mostly towards the base. 

 (Lessons, Figs. 266, 267 ; the akene, Fig. 380.) 



* * * Pappus of rather numerous and stout long-phimose bristles. 



T2. TRAGOPOGON. Head large, of many yellow or purplish flowers. Involucre of about 



12 lanceolate rather fleshy scales in a single row, somewhat united at the base. 



Akenes terete, slender, roughish, tapering into a long beak, which bears the rigid 



long-plumed bristles of the pappus, 5 of these longer and naked at the summit. 



Stems leafy; leaves entire, parallel- veined, clasping at the base. 

 78. LEONTODON. Head rather small, of many yellow flowers. Involucre of many 



narrow equal erect scales, and a few short bractlets at base. Akenes spindle-shaped ; 



pappus a single row of tawny plumose bristles. Leaves all at the root, or base of the 



scapes. 

 » * * * Pappus many slender, but rather st-ffland rough, tawny, not plumose bristles. 



74. HIERACIUM. Heads small or smallish, of 12 or more yellow flowers. Scales of the 

 involucre unequal and in more than one row. Akenes short, oblong or columnar, 

 not beaked ; the fragile bristles of the pappus not very copious. Stems naked or 

 leafy. 



76. PRENANTHES. Heads usually nodding, of 5-40 greenish-white or yellowish, often 

 purple-tinged flowers. Involucre cylindrical, of 5-15 linear scales in a single row 

 and a few short bractlets at base. Akenes cylindrical ; pappus of very copious straw- 

 colored or brownish bristles. Stems leafy. 



* * * * * Pappus of extremely copious, and fine, soft, hair dike, not plumose, bristles. 



+- Mature akenes with the pappus raised on a very slender (short in some Lactucas) 

 stalk-like beak. 



76. PTRRHOPAPPUS. Head of yellow flowers as in the next ; but the pappus rusty red 

 and with a minute ring of soft down underneath it. Stems branohing and leafy near 

 the base, the long peduncles naked. 



