COMPOSITACEAE (COMPOSITE FAMILY) 237 



MM. Akenes somewhat flat. 

 P. Akenes beakless, truncate; heads 50-floweredor more. SONCHUS (p. 237) 

 PP. Akenes beaked or attenuate; heads 6-30-flowered. LACTUCA (p. 238) 



AA. Flowers white or pink or blue or purple; stems leafy or bracted. 

 Q. Pappus a crown of short blunt scales; heads sessile or nearly so, in spikes or 

 racemes. W. — Root a substitute for coffee. (From chikouryeh, its Egyptian 

 name.) Cichorium intybus (chicory) 



QQ. Pappus of simple bristles though often scabrous. 



R. Flowers white; leaves and lower part of stem with long white stiff spreading 

 hairs; leaves lanceolate to oblong, entire. HIERACIUM (p. 238) 



RR. Flowers not white; plant without long white stiff spreading hairs; leaves 

 usually not as described above. 

 S. Leaves entire, lanceolate or narrower, not sagittate at base; flowers rose- 

 colored or pink; akene terete, neither fiat nor angled. E. — (Gk. lygos = a. twig, 

 desma = a bundle; referring to the tufted rushlike stems.) Lygodesmia 



SS. Leaves either not entire or else sagittate at base; flowers pink or blue or 

 purplish; akene terete or 4-5-angled or somewhat flat. 

 T. Akene terete or 4-5-angled, not flat; pappus tawny; leaves deltoid-hastate 

 but becoming narrower up the stem; plant 3-6 dm. high. W. C. — (The 

 Latinized Indian name for the Rattlesnake-root.) 



Nabalus faastatus {rattlesnake root) 

 TT. Akene somewhat flat; pappus white; leaves several times as long as wide; 

 plant usually taller. LACTUCA (p. 238) 



QQQ. Pappus of plumose bristles. 



V. Heads solitary and terminating a leafy stem, 5-10 cm. wide; leaves all entire; 

 akene with long slender beak; flowers purple. W. E. — Cultivated as a vegetable 

 for its root. (Gk. iragos = a goat, pogon = a beard; referring to the con- 

 spicuous tawny pappus.) Tragopogon porrifolla (oyster plant) 

 TTO". Heads in panicles or corymbs, 2.5 cm. or less wide; mostly with at least the 

 basal leaves not entire; flowers pink or white. 

 V. Akene tapering into a slender beak as long as the body; involucre 18-25 mm. 

 high, 15-30-flowered. E. — ^^(Probably in honor of C. S. Rafinesque, an American 

 botanist.) Rafinesquia calif oroica 

 W. Akene truncate, beakless; involucre 6-15 mm. high, 3-6-flowered. E. — (Gk. 

 ptilon = a feather; referring to the pliunose pappus.) Ptiloria 



SONCHUS (Sow Thistle) 



Stem leafy. Leaves mostly auriculate-clasping, entire to pinna tifid, 

 prickly-margined. Heads in corjmibs or panicles; receptacle naked. 

 Corolla yellow. Pappus of bristles ; bristles many, white, capillary, simple. 

 — (Gk. sonchos = hollow ; referring to the stem.) 



A. Involucre glandular-pubescent, 25 mm. high; flowers bright yellow; perennial; 

 leaves with acute basal angles; akenes transversely wrinkled. W. E. 



S. arvensis (field sow thistleI 

 AA. Involucre glabrous, 12-16 mm. high; flowers pale yellow; annual. 

 B. Leaves with acute basal angles; akenes transversely wrinkled. W. 



S. oleraceus (common sow thistle) 

 BB. Leaves with rounded basal angles; akenes not transversely wrinkled. W. E. 



S. asper (prickly sow thistle) 



