170 Rydberg : Studies on Rocky Mountain Flora 



the very- first, pinnately divided : heads rather small and minutely 

 calyculate. In habit resembling the Aurei and Tomentosi, to 

 which the last two form a transition, but have more divided leaves 

 and a root of less duration. 



Leaves thin ; root annual or biennial. 



Head about I cm. high ; terminal segments of the basal leaves 3-5 cm. wide. 



1. S. sangiiisorboides. 

 Head 5-8 mm. high ; terminal segments of the basal leaves less than 2 cm. wide. 



Basal leaves with few segments ; segments crenate or dentate. 



2. S. Greggii. 

 Basal leaves with numerous segments ; segments lobed or cleft. 



3. S. millelobatus. 

 Leaves rather thick ; root perennial. 



Bracts thick, much shorter than the disk. 4. s. multilobatus. 



Bracts thin, almost equaling the disk. c s, NelsoniL 



■ 



1 . Senecio sanguisorboides sp. nov. 



Tall and simple, perfectly glabrous, annual or maybe biennial : 

 stem terete, about 6 dm. high, leafy : basal leaves thin, 1-2 dm. 

 long, petioled, pinnately divided with 3-5 segments ; terminal seg- 

 ments reniform, 3-5 cm. wide, coarsely crenate ; lateral segments 

 almost orbicular, crenate : lower stem leaves similar ; the upper 

 with 7-1 1 segments, short-petioled or the uppermost ' subsessile ; 

 the base of the petioles with large round, laciniate auricles ; ter- 

 minal segment ovate, incised-crenate ; the lateral ones obovate 

 or broadly cuneate : cyme rather contracted : heads about 1 cm. 

 high; bracts 12-16, linear-lanceolate, acute, about 1 mm. wide, 

 with membranous margins; the calyculate ones very few and 

 minute, lanceolate : rays about 10, 8 mm. long and 3 mm. wide, 

 about 4-nerved : achenes glabrous and angled. 



This has been referred to .S". Satiguisorbae DC; but a compari- 

 son with De Candolle's description shows several discrepancies. 

 According to the description S. Sanguisorbae should have only 

 8-10 bracts and 5 rays, the leaves should be puberulent beneath 

 and the terminal segment orbicular, characters not found in the 

 present species. The latter grows at an altitude of 2 



m. [Plate 5, f. 14.] 



00- 



New Mexico: Santa Fe Canon, 180,7 A. A. & 



Ht 



121 



2. Senecio Greggii sp. nov. 



Senecio Tampicanus A. Gray, PL Fendl. 109. 1849; not DC. 

 1837; 5. lobatus A. Gray, PI. Wright. 2: 99. 1852; not 

 Pers. 1807. 



