OF ARTS AND SCIENCES. 9 



Encelia cordata^ Hemsley). The root is annual ; the involucre be- 

 tween hispid and hirsute ; and the akenes obovate-oblong, with shallow 

 notch, pilose-pubescent on the faces, more ciliate towards the summit ; 

 awns of the pappus rather lon^, with more or less scarious-dilated base 

 often fringed with two or three teeth or setae on each side. 



Encelia lagasc^fokmis ^Simsia, DC.) is taken up by Hemsley 

 from my naming after Bentham ; but the plants of Hartweg, of Ervend- 

 berg, and of Parry & Palmer, cannot be DeCandolle's. They have 

 rather the characters of E. Mexicana in a depauperate state. DeCan- 

 dolle's species is much better represented by a specimen in our herba- 

 rium — an imperfect one — from Botteri's collection around Orizaba ; 

 slender, with small and narrow heads, an involucre which accords 

 with DeCandolle's character in having (broadly) lanceolate bracts, the 

 outer only half the length of the inner (but these are villous rather 

 than hispid), the pays " about 5 " and exserted, the akenes quite gla- 

 brous. As the awns are wanting in the specimen, this may be identi- 

 cal with Bourgeau's 3320, referred by Hemsley to E. exaristata, to 

 which it is obviously related. 



Encelia heterophylla, Hemsley, 1. c, I know only from the fig- 

 ure of Ximiiiesia heterophylla, HBK. It is said to be perennial and 

 yellow-flowered. One may suspect that E. sanguinea, Hemsley 

 {Simsia sanguinea, Gray, PI. Wright, i. 107, also distributed by Schultz 

 Bip. as S. erythranthema) is only a red-flowered variety of it. 



Encelia Ghiesbreghtii, Gray, Proc. Am. Acad. viii. 658, has a 

 peculiar habit, in foliage and pubescence agreeing well with the descrip- 

 tion of E. sericea, Hemsley, 1. c. It is probably a perennial. The 

 fruit is not sufficiently developed to make sure of the genus. 



Helianthella § Enceliopsis. a subgenus formed for the 

 reception of two anomalous scapose perennials, thick-leaved, silvery- 

 canescent, with large solitary heads (the disk an inch broad and flat) ; 

 paleae of receptacle soft and scarious ; achenia flat, oblong-cuneate, 

 very villous, with narrow callous margins and summit, the latter bor- 

 dered between the short subulate awns by a very short fringe of 

 membranaceous and confluent squamella^. 



H. nudicaulis. Encelia ( Geroea) nudicaulis, Gray, Proc. Am. 

 Acad. viii. 656. Mr. Shockley has recently sent it from the western 

 part of Nevada. 



H. ARGOPHTLLA. Tithoma argophyUa, Eaton in Bot. King. 423. 

 Encelia ( Germi) argophylla, Gray, 1. c. This is still imperfectly known. 



Helianthella proper. In revising this genus I find that the 

 following species may be associated as having soft-scarious chaff of 



