21 



A NEW SENECIO FROM PENNSYLVANIA 



By N. L. Britton 



In the course of a field excursion of the Torrey Club and the 

 Philadelphia Botanical Club on May 29, 1899, at Penn Valley 

 and Tullytown, Bucks Co., Pa., my attention was called by 

 Mr. Joseph Crawford to a Senecio growing in abundance in a 

 marshy meadow at Tullytown, which seemed different from any 

 described species. The plant was in full flower at the time and 

 its bright yellow rays were a conspicuous feature in the land- 

 scape. Ripe fruiting specimens were secured from the same 

 place by Mr. Crawford on June 6, 1900. 



The locality had already been considerably explored by the 

 Philadelphia botanists and is interesting from the large number 

 of pine-barren plants which inhabit it, the soil being very sandy. 



The new species resembles both Sejtecio Balsamitae Muhl., of 

 dry soil, and vS Robbinsii Oakes, of northern meadows, but is, I 

 think, distinct from either. I append a description. 



Senecio Crawf ordii. — Perennial, with slender thread-like roots, 

 glabrous, or with sparse woolly pubescence below. Stem slen- 

 der, about 4 dm. high : leaves thick, firm, the basal ones erect, the 

 larger 2—2.5 dm. l° n g> the blades oval, oblong, orsome of them 

 narrowly obovate, mostly not more than one-half as long as the 

 slender petioles, sharply and nearly equally serrate from the acute 

 or obtuse apex to the entire cuneate base, or the lower teeth 

 somewhat larger than the upper ; stem leaves lanceolate or nar- 

 rower, mostly acuminate, incised-serrate, clasping, the upper ses- 

 sile, the lower petioled, the uppermost very small : heads 3—7 ; 

 peduncles 1.5— 10 cm. long, slender, bracted, rarely forked ; in- 

 volucre 7-9 mm. high, its bracts linear-lanceolate, acuminate, 

 1 -1. 5 mm. wide, shorter than the white barbellate pappus ; rays 

 8—10 mm. long; achenes linear, striate, 2.5 mm. long, 0.5 mm. 

 thick. 



Type specimens in herbarium of the New York Botanical 

 Garden. 



