310 DESCRIPTIONS OF NEW SPECIES 



1 1 Leaves dissected. Achenium not striated, rays rather numerous. Pappus 

 double, the setce barhellated. (Tridactylta.) 



Erigeron compositum. (Pursh, Vol. II., p. 535.) Pappus double in ray and 

 disk, the outer short, entire, the inner of eighteen to twenty barbellate, decidu- 

 ous rays. 



Hab. Kamas prairie, in the Rocky Mountains. Flowering in June. 



^. PHiENACTis, {Stenactis in part.) — Pappus persistent and scabrous, of fif- 

 teen to twenty-four setge, external minute pappus simple; achenium com- 

 pressed, with three to five striae, radial florets very numerous. — Perennial,, 

 with entire leaves. 



Erigeron speciosum, (Decand., Vol. V., p. 284.) Obs. — Pappus double both 

 in ray and disk; the exterior short and subulate. Stenactis speciosa, (Lind. 

 Bot. Reg. t. 1577.) Common on the plains of the Oregon. 



Erigeron macranthum; smooth, lower leaves spathulate-oblong, obtuse, at- 

 tenuated at base; stem leaves elliptic-ovate, or ovate, abruptly apiculate, sca- 

 brous on the margin; peduncles few, one-flowered, corymbose; rays a little 

 longer than the disk; sepals narrow and acuminate, glandular. — Erigeron 

 grandijlorum, Nutt. in Journ. Acad. Nat. Sci., Vol. VII., p. 31, not of Hooker. 



Hab. Sources of the Missouri and the plains of the Platte. Flowering in August. Allied to 

 the preceding. Rays numerous, blue. About eighteen inches high. Flowers four or five on a 

 stem. 



Erigeron *hispidum; stem erect, corymbose, above scabrous and hispid ; leaves 

 entire, ciliate and scabrous on the margin, radical spathulate,^ cauline sessile, 

 acuminate; peduncles elongated, one-flowered; sepals of the involucrum hoary, 

 hispid, very hirsute, much acuminated ; rays very numerous. 



Hab. St. Barbara, Upper California. Nearly allied to E. speciosum, from which, however, it 

 is very distinguishable by its exceedingly hirsute involucrum, and hispid, naked, elongated pedun- 

 cles ; the leaves appear, also, broader, and scabrous towards the points. Rays blue, more nume- 

 rous than in speciosum, and not so long. Pappus double in ray and disk ; rays twenty to twenty- 

 four, persistent. 



Erigeron *maritimum; stem pilose, decumbent, branching from near the base ; 

 leaves thick and entire, spathulate-oblong, sessile, obtuse, the lower narrowed 

 at base; branches several, one-flowered, flower large, rays very numerous; in-^ 

 volucrum lanuginous as well as the margins of the leaves, sepals acuminate. 



