CICHORIACEAE. 403 



Heads solitary on leafless scapes. 12. NOTHOCALAIS. 



Beaks of the achenes distinct and slender ; plants scapiferous. 



Achenes lo-ribbed or lo-nerved, not spinose-muricate ; involucres more 



or less imbricated. 13. AGOSERIS. 



Achenes 4-s-ribbed, muricate-spinulose at least near the apex; in- 

 volucres of a single series of principal bracts and several or numer- 

 ous calyculate ones below. 14. TARAXACUM. 

 2. Achenes flattened ; leafy-stemmed plants with paniculate heads. 



Achenes narrowed at the top or beaked ; pappus-bristles falling separately ; 



involucres cylindraceous. 15. LACTUCA. 



Achenes truncate at the top ; pappus-bristles falling off more or less in 

 connection ; involucres hemispherical or campanulate. 



16. SONCHUS. 



i. PTILOCALAIS Greene. 



i. Ptilocalais nutans (Geyer) Greene. (Microseris nutans A. Gray) Wet 

 meadows from Mont, and Wash, to Colo, and Calif. Alt. 8000-10,000 ft. 

 Minturn, Eagle Co. ; Cerro Summit ; Silver Plume. 



2. PTILORIA Raf. 



Perennials. 



Pappus plumose to the base, white ; leaves, at least the lower ones, broad, 



oblanceolate in outline and runcinate. i. P. ramosa. 



Pappus merely scabrous at the base, brown ; leaves often runcinate, but narrow. 



2. P. pauciftora. 

 Annuals or biennials. 



Pappus plumose to the base, not paleacous-dilated ; plant strict, virgate ; leaves 



entire or sinuate. 3. P. virgata. 



Pappus plumose above the middle, dilated and paleaceous at the base ; leaves 



pinnatifid or bipinnatifid or the upper bract-like. 4. P. exigua. 



1. Ptiloria ramosa Rydb. On dry plains and in "bad-lands" from Neb. 

 and Mont, to Colo. Alt. 4000-6000 ft. New Windsor; Boulder. 



2. Ptiloria pauciflora (Torn) Raf. (Stephanomeria runcinata Nutt.) On 

 plains and hills from Colo, and Nev. to Tex. and Ariz. Alt. 4500-8000 ft. 

 Buena Vista; Villa Grove; Mancos; Ft. Collins; Grand Junction; Deer Run; 

 New Windsor; near Boulder; Hotchkiss; Cucharas Valley, near La Veta ; 

 Canon City; between Sunshine and Ward; Boulder. 



3. Ptiloria virgata (Benth.) Greene. (Stephanomeria virgata Benth.) In 

 arid places from Colo, and Nev. to Calif. Alt. about 4500 ft. Grand Junc- 

 tion. 



4. Ptiloria exigua (Nutt.) Greene. Dry places from Wyo. to N. M., Calif, 

 and Nev. Grand Junction (Eastzuood). 



3. TRAGOPOGON L. SALSIFY, OYSTER PLANT. 



Flowers yellow ; involucral bracts equalling or shorter than the ligules. 



1. T. pratense. 

 Flowers purple ; involucral bracts much longer than the ligules. 



2. T. porrifolius. 



1. Tragopogon pratensis L. In fields and waste places from N. B. and Man. 

 to N. J. and Colo. ; naturalized from Europe. Ft. Collins ; Boulder. 



2. Tragopogon porrifolius L. In fields and waste places from Out. and 

 Minn, to N. C. and Colo. Escaped from cultivation. Ft. Collins ; Colorado 

 Springs. 



