OF ARTS AND SCIENCES : MAY 13, 1873. 665 



Tithonia Thurberi. Caule gracili superne hispido ; foliis ovatis 

 indivisis ; capitulo pro genere p£.rvo ; involucri squamis obtusis, exteri. 



§ 2. Achenia angustiora angulis acutis, dis •. salte.a lateraliter compressa. 



Capitula mediocra, nuda, rarius basi foliata. 

 * Albo-tomentosa, vel demum glabrescens, foliis latis petiolatis, caule nunc 



ramoso. 



3. "W. oyata Gray, 1. c. 7, p. 357. Tomentoso-pubescens ; foliis lato-ovatis 

 cordatisque ; involucri lato-hemisphnsrici squamis plurimis apice patentibus ; 

 pappo paleaceo-calycitbrmi brevi exaristato. 



4. W. mollis Gray, 1. c. 6, p. 55-4. Albo-lanata, nunc glabrescens ; foliis 



oblongis summisve ovatis reticularis; involucri campanulati squamis 10-12 



latioribus erectis discum superantibus ,• pappo piaster coronulam truncatam 2-5- 



aristato. 



* * Glaberrima, foliis angustioribus, caulinis sessilibus. 



5. W. amplexicaclis Nutt. Involucrum campanulatum. Pappus vix ac ne 



vix aristiformis. 



* * * Hirsuto-pubescens, foliis lanceolatis. 



6. W. btelianthoides Nutt. Pygmaea, pube laxa subvillosa ; involucro etc. 

 subsequentis ; pappo brevi exaristato rariusve arista unica gracili. — This is Nuttali's 

 original Wyethia, founded on specimens, in flower only, collected by Wyeth " in 

 the Valleys of the Rocky Mountains near Flat-Head River" (as it would appear 

 in about lat. 47° long. 114°), to which Nuttall afterwards added a plant collected 

 bv himself " near the Blue Mountains of Oregon." The species is imperfectly 

 known, and seems to differ from the next mainly in the awnless'or occasionally 

 one-awned pappus. I cannot well examine the interior of the single capitulum of 

 Wyeth's specimen in our herbarium. A few separate flowers from one of Nuttali's 

 own collecting are awnless. 



7. W. angustifolia Nutt. Spithamaea ad ultrapedalem ; foliis radicalibus 

 elongatis utrinque attenuates ; involucro polyphyllo patente, squamis plerisque 

 foliaceis lato-linearibus nunc subspathulatis ssepius obtusis aut undique aut ad 

 margines pilis longis hirsutis ; acheniis interioribus 1-2 extimis saepius 3-4- 

 aristatis, arista valida hirta. Alarconia angustifolia DC. Wyethia robusta Nutt. is 

 merely one of the larger forms of this common species of California and Oregon. 



8. W. Akizoxica. Pedalis, scabro-hirsuta ; caule 1 - 2-cephalo ; foliis oblon- 

 go-lanceolatis integerrimis, superioribus sessilibus ; capitulo parvulo ; involucro 

 hemisphaerico, squamis oblongo- seu ovato-lanceolatis (lit videtur erectis) pilis 

 brevibus cinereo-hirsutis ; corolla? dentibus extus hispidulis; ligulis circiter 10 

 (subpollicaribus) ; acheniis immaturis fere praecedentis. In pine woods and bot- 

 toms, near Bear Springs, Northern Arizona, Dr. E. Palmer. Also Southern Utah, 

 Captain F. M. Bishop ; a less hirsuie form. 



#** * Hispido-scaberrima, foliis linearibus, ligulis nullis ? 



9. "W. scabra Hook. Lo.nd. Jour. Bot. 6, p. 245; Gray in Bot. "Whippl. p. 46 

 (102). This little known species of Utah ? and New Mexico, is peculiar in habit* 

 and perhaps in the absence of rays ; very likely it is not of this genus. 



