Rydberg : Studies on Rocky Mountain Flora 171 



Biennial or annual, with several stems from the base, perfectly 

 glabrous in age : stems about 3 dm. high : leaves pinnately divided 

 or the very first ones simple : basal leaves with 3-5 segments, the 

 terminal one round and crenate, about 1 cm. in diameter; the 

 lateral ones small, obovate ; stem leaves with 7-9 small segments 

 and more or less auricled at the base of the very short petiole : 

 cyme compound : heads rather many, only 5-7 mm. high ; bracts 

 about 20, linear-acuminate ; the calyculate ones minute and few : 

 rays 8-10, about 3 mm. long and 1.5 mm. wide, 3 -nerved : 

 achenes angled and strigose. 



This is nearest related to 5. lobatus but smaller and characterized 



by the many stems from the same root, the few segments of the 



basal leaves, the small heads and the narrow bracts. Only 



Wright's specimens were collected in the region here treated. 

 [Plate 5, f. 8.] 



Mexico : Santa Rosalia, Dr. Gregg (type in Torrey Herba- *&*t 

 rium). - - 



Texas: Near El Paso, 1851-2, C. Wright, 141 3; between &) "' 



4U tiC 



Frio and Nueces Rivers, 1880, E. Palmer, 754.; Loredo to Frontera, ^' ;< l 



Wr 



'*>% 



A 



3. Senecio millelobatus sp. no v. 



</ 



99. 1852 ; not DC. 



1 ^37 ; S- midtilobatus A. Gray, Syn. Fl. I 2 : 394, in part. 1884 ; 

 not T. & G. 1 849. 



Annual or biennial, perfectly glabrous or slightly floccose at 

 the base of the leaves : stem branched, 3-5 dm. high, very leafy : j 



all leaves pinnately divided, 3-7 cm. long, lanceolate or oblanceo- 

 late in outline ; segments 13-23, obovate, 3-10 mm. long, lobed or 

 cleft into oblong or ovate lobes ; the upper segments more or less 

 confluent : cyme compound : heads about 8 mm. high ; bracts ob- 

 long-lanceolate, acuminate, 1 2—1 5 in number; calyculate ones 

 minute and few : rays 5-8 mm. long and 1.5-2 mm. wide : achenes 

 very scabrous on the angles. 



This is nearest related to the preceding and to S. lobatus but is 

 easily distinguished by the numerous and lobed or cleft segments. 

 It may be related to 5. Tampicanus which I have not seen, but that 

 species is described as having only 4 or 5 pairs of segments and 

 glabrous achenes. [Plate 5, f. 11.] 



M 



Hills on the Limpia, 185 1-2, C Wright, 12S7 % £ft 



(type in the Torrey herbarium) ; P. V. Lc Roy. 





