277 Rydberg: Studies on the Rocky Mountain Flora 



sparingly puberulent on both sides, divided to the base into 5-7 

 segments, which are 6—12 cm. long and twice cleft into linear lobes 

 3-5 mm. broad : inflorescence branched, densely many-flowered : 

 pedicels 1-3 cm. long, rather stout, usually equalled or surpassed 

 by the linear bracts : bractlets filiform, 5-10 mm. long, inserted 

 close under the calyx : sepals dark blue, paler at the base, ellipti- 

 cal, all except the upper one obtuse, 12-15 ^n"^- lo"g ; spur 12 

 mm. long, slightly curved : upper petals narrow, light brownish, 

 striate: lateral petals with slender claws bent at right angles, 

 bearded only within, deeply 2 -cleft at the apex. 



This species in perhaps closest related to D. cncidlatiivi A. 

 Nelson but differs in the longer and narrower leaf-segments, the 

 more branched inflorescence, the stouter habit, the longer bracts 

 and bractlets and narrower upper petals. It grows at an altitude 

 of about 2500 m. 



Colorado : Wahatoya Creek, below the Spanish Peaks, 1900, 

 Rydberg & Vreeland, 621 y (type); Colorado Springs, 1895, E. A. 

 Bessey ; Ruton, 1840, Albert. 



Erysimum alpestre (Cockerell) 



Erysijimrn aspenini f. alpestre Cockerell, Bull. Torr. Club, 18 : 

 168. 1891. 



A tall strigose perennial with a deep tap-root ; stem strict, sim- 

 ple, 3-6 dm. high, striate : basal leaves linear or narrowly linear- 

 oblanceolate, 5-10 cm. long, 2-7 mm. wide, subentire or sinuately 

 denticulate, grayish strigose, gradually tapering below with a short 

 petiole : stem leaves mostly narrowly linear, the upper sessile : 

 raceme at first short and corymbiform, in fruit much elongated : 

 pedicels short, in fruit scarcely i cm. long, ascending: calyx 10- 

 1 2 mm. long, yellow : two of the sepals strongly saccate at the 

 base : petals with slender claws : blades broadly obovate-cuneate, 

 slightly emarginate, about 8 mm. long and broad, varying from 

 orange or brown to rose-purple or the older pale yellow : pods 

 four-angled, slender, erect, J-^ cm. long and 1.5 mm. in diameter : 

 style about 2 m.m. long, stout. 



In general habit, this species closely resembles E. aspenun. 

 Mr. Cockerell, who seems to have been the first to observe this in- 

 teresting plant of the Sangre de Christo region, took it to be a form 

 of E. asperiini with peculiarly colored petals, found only at high 

 altitudes. I was first of the same opinion until I saw the fruit 

 in the type number and still better developed in Mr. Bessey's 



