142 



Probably nearest related to Carduus oreophlius Rydb. Col- 

 lected in the canyon of the Thompson river, between the foot- 

 hills and Estes Park, Larimer county, Colorado, August i6, 

 1905, no. 3090. 



Ptilocalais tenuifolia 



One to three scapose stems 1-2 dm. high from a fusiform 

 root, surrounded at the base by narrowly linear leaves 2 mm. 

 wide and i cm. or more long, entire or some of them having dis- 

 tant down-pointing linear lobes, the stem also bearing one or 

 two similar leaves: each stem bearing a single head or sending 

 out one or two branches from the axils of the leaves: the whole 

 plant glabrous except some slight dark pubescence on the in- 

 volucre: the involucre 12-15 mm. long in two series of 12-15 lin- 

 ear acuminate bracts, with a few calyculate ones at base: achenes 

 striate, truncate at summit, 5 mm. long and slightly attenuate 

 downward: pappus of 15-18 plumose sordid bristles, paleaceous 

 at base, each bristle about 7 mm. long, the paleaceous portion a 

 little more than i mm. long. 



Collected at Sulphur Springs, Grand county, Colorado, June 

 28, 1905, no. 2998 — a fruiting specimen — and in flower at the 

 same place June 11, 1906, no. 3235. Readily distinguished 

 from Ptilocalais nutans (Geyer) Greene, by the narrow leaves 

 and sordid pappus. 



Crepis exilis 



Seemingly a perennial, one or two slender stems from a 

 tap-root, cinereus pubescent, becoming glabrate: leaves mostly 

 at the base with scarious sheaths and short petioles, laciniate 

 pinnatifid, i dm. long or some of them a little longer, tapering 

 into a rather slender prolongation, the main body of the leaf 

 4-5 mm. wide, the linear lobes i cm. long; two or three stem 

 leaves similar but much reduced in size, and the uppermost lan- 

 ceolate and entire: stem branching at the top and having 3-5 

 heads on moderately short peduncles: principal bracts of the in-p 



