98 PROCEEDINGS OP THE AMERICAN ACADEMY 



§ 6. EuASTER, or Aster proper. This includes all the remain- 

 ing perenniitl Asters which have partly herbaceous or foliaceous, or at 

 least herbaceous-tipped involuci'al bracts, and a simple pappus. 



§ 7. DcELLiNGERiA, adopted from Bentham and Hooker, is marked 

 by the short involucre of thin coriaceous inappendiculate bracts, and 

 a double pappus, the outer like that of many species of Erigeron, the 

 larger bristles of the inner commonly clavellate-thickened at apex ; 

 the rays, as in § Biotia, are few. A. injirmus, Miclix. (a somewhat 

 earlier name than A. cornifolius, Muhl.), A. umhellatus, Mill, (which 

 includes A. amygdalinus), and the somewhat ambiguous A. reticu- 

 latus, Pursh, are the species. 



§ 8. Ianthe, taken from Torr. & Gray, Fl., includes a few species 

 with pappus inconspicuously double, the outer being slender-setulose 

 or indistinct, the bristles of the inner not at all clavellate ; the 

 involucre, &c. that of the following section. (A. ohovatus, Meyer, the 

 Rhinactina limonifolia, Less., lies between this section and the pre- 

 ceding.) Our species are A. Unariifolius, L., A. scopulorum (the 

 Chrysopsis alpina and Diplopapp^is cdpiniis of Nuttall), and A. ericce- 

 folius of Rothrock, which is the Diplopappiis ericoides of Torrey and 

 Gray. 



§ 9. Ortiiomeris is taken from Torrey and Gray, Fl., with some 

 extension. It includes the remainder of our perennial Asters, those 

 with simple pappus and no green tips to the involucral bracts. A. 

 acuminatus, Michx., and A. nernoraUs, Ait., make the first section. 

 Another consists of A. Engelmanni, Gray, A. ledophtjUas (promoted 

 from the variety of the preceding), and A. elegans, Torr. & Gray, 

 three very close species, and A. glaucus, Torr. & Gray. A. ptarmi- 

 coides, which forms another section, has a var. Georgianus, remarkably 

 tall and branching, from the mountains of Georgia, where Dr. Chap- 

 man collected it ; the Xylorrhiza section has a proposed new species, 

 A. 'Watsoni, founded on a plant referred to A. glacialis by Eaton 

 in Bot. King (no. 509) : it may pass into A. arenarioides, Eaton. The 

 remaining section consists of species which had been referred to Oxy- 

 tripoUum. The last of them is A. tenuifolius, L. (not of subsequent 

 authors), which is A. Jlexnosus, Nutt., and which differs from tlie fol- 

 lowing only by the perennial rootstock. 



The series of monocarpic (annual and biennial) Asters contains the 

 following subgenera or primary sections, besides TripoUum of the Old 

 World. 



§ 10. OxYTRiPOLiUM. TripoUum § Oxytripolia, DC, excluding the 

 perennial species. It is suspected that the widely distrilmted warm- 



