CICBOEIACEAE. ;*09 



6. TBAGOPOGON L. Goat 's-beard. 



Mowers yellow; involucral bracts equalling or shorter than the' rays. 



1. T. pratensis. 

 Flowers purple; involucral bracts much longer than the rays. 



2. T. porrifoliitt. 



1. Tragopogon pratensis L. Yellow Goat 's-beard. M. p. 895. Fields and 



waste places. Summer and fall. 

 Delaware— Wawa. 



2. Tragopogon porrifolius L. Oyster-plant, Salsify. M. p. 895. Escaped 



from cultivation. Summer and fall. 



Philadelphia— Girard Point (Ja.), "Neck" (VP.).. Bucks— Sellers- 

 ville (Fr.) (Ja.). Montgomery — Betzwood (Br.), Ivy Rock (Wn.). 

 Delaware — Swarthmore (Pr.) (Ws.), Concord (W. Tr.). Northampton — 

 (P.). 



Monmouth— Freehold (C). Hunterdon— Eosemont (C). 



7. TARAXACUM Hall. Dandelion. 



Achenes greenish. 1. T. Taraxacum. 



Achenes red. 2. T. erythrospermum. 



1. Taraxacum Taraxacum (L.) Karst. M. p. 896. Fields and waste 



places. All year. 



2. Taraxacum erythrospermum Andrz. M. p. 896. Fields and woods. 



Spring. 



8. SONCHUS L. Sow-thistle. 



Involucre glandular-pubescent; heads nearly 25 mm. high. 1. 5. arvensis. 

 Involucre glabrous; heads 12-16 mm. high. 



Auricles of leaves acute, achenes striate and transversely wrinkled. 



2. S. oleraceus. 

 Auricles rounded; achenes ribbed, not transversely wrinkled. 



3. S. asper. 



1. Sonchus arvensis L. M. p. 897. Salt marshes and ballast. Summer. 



Philadelphia— "Neck, " Louis Schneider (Ja.). Northampton— (P.). 

 Camden— Kaighn's Point. Cape May — Cape May (Te.). Monmouth — 

 Asbury Park (Br.) (Fu.) (Wn.), Atlantic Highlands, Scobyville (C). 

 New Castle— Corn-fields near Collins' Beach, Commons and Tatnall. 



2. Sonchus oleraceus L. Common Sow-thistle. M. p. 897. Waste places 



and cultivated grounds. Summer and fall. 



3. Sonchus asper (L.) All. M. p. 897. Waste plaees. Summer. 



9. LACTUCA L. Lettuce. 



Pappus bright white. 



Leaves spiny-margined and often with spiny or hispid midribs; flowers 

 . yellow. 

 Heads 6-12-flowered ; involucre very narrow, 8-12 mm. high. 



1. L. virosa. 

 Heads 12-20-flowered ; involucre broader. 4. L. sagittifolia. 



Leaves neither spiny-margined nor with spiny midribs (rarely spinulose 

 in No. 3). 

 Achenes very thin, flat, contracted into filiform or tapering beaks. 

 Leaves, or some of them, pinnatifid. 



Plant glabrous throughout, 1-3 mm. high. 



2. L. Canadensis. 



