Lygodesmia.] COMPOSITiE. 295 



of frequent occurrence iu the British Possessions. But I believe I am not singular in thinking- that it may 

 be a variety oi N, albus, to which N. cordatus and altissimus are too closely allied j from which a^in our 

 iV. alatus is chiefly to be distinguished by its winged petioles. Prcenanthes virgata of Michaux, P. rubicunda 

 of Willdenow, and P. simplex of Pursh may perhaps, with equal safety, be referred to N. albus. 



3. LYGODESMIA. Don, 



Jnvolitcrum pentaphyllum, tubulatum, basi squamulis plurimis brevissimis imbricatis 

 munitum, foliolis ligulatis carinatis margine scariosis. Eeceptnculum scrobiculatum. 

 Flosculi 5. AnthercB basi bidentatae. Achenia linearia compressa sulcata apice simplicia. 

 Pappus capillaris: radiis multiplici ordine copiosissimis (vel paucis) dcnticulato-scabris 

 (plumosisve)subpersistentibus. — SufFrutices (seMherbse) Amer, Bor. et Syri^, facie Ephedrte, 

 ramosissimi apkylli (in L, juncea evidentissime foUosi) squamis (foliorum rudimentis) 

 suhulaiis^ patulis sparsis, Flores soUtarii sessiks. Pappus carnomsfuscescens, Don* 



1. L,jumea; caule ramosissimo striate, foliis lineari-subulatis, pappi pilis numerosissiniis 



scabris. (Tab. CIII.) — Don, in Ed, N, Journ. of Sc. 1829, p, 311.— Preenanthes juncea. 

 Pursh, FL Am. v. 2. p, 498. 



Radix subfusiformis, longa, ut videtur, perennis, Caidis crectus vel subdecumbens, herbaceus, pedalis 

 ad bipedalem, per totam longitudinem ubique valde ramosus, striatus, subglaucus, ramis erectls vel flexuosis, 

 longis, subvirgatis. Folia altema, fere omnino ad insertionem rumorura, rigida, subglauea, liueari-subulata, 

 striata, integerrima, sessilia sed non amplexantia; inferiora 2 uncias longa, superiora sensim minora. Rami 

 ultimi, seu pedunculi, graciles, uniflori, bracteis seu foliis parvis subulatis suffulti. Flores terminales, nnciam 

 longi, ca?nilei. Involucrum cylindraceum, e foliolis 5, erectis, lineari-oblongis, membranaceis, margine 

 subscariosis, basi squamosis; squamis erectis, imbricatis, brevibus, Flosculi 5, majuscuU. Corolla llgiilata, 

 lata, 5-dentata. Starninuni tubus elongato-cylindraceus : Antkerce basi utrinque breve calcarata;. Sij/lus 

 inclusus. Stigmata exserta, linearia, erecto-patentia, glanduloso-pubescentia. Achenia oblonga, striata, 

 ad orem dilatata. Pappus sessilis e pilis numerosissirais sub lente scabris. 



Hab. Dry plains of the Saskatchawan. Drummond. — There is a peculiarity in the habit of this plant, as 

 Mr. Don justly observes; and I have adopted that Botanist's genus and character of Lj/godesmia, 

 including, indeed, the Prcenanthes triquetra of Labillardiere, a Syrian plant, with which I am unacquainted. 

 The American P.pumila, Baldw. mentioned by Don, (I presume the P. aphylla of Nuttall, Nov. Gen. v. 2. 

 p. 123,) is equally unknown to me. With the exception of the leaflets of the involucre not being carinated 

 in our L.jiinceOy it agrees in every point with Mr. Don's Li/gndesmia : but a second species, next to be 

 mentioned, has a pappus of a very different character, yet is unquestionably the same genus. In neither, 

 however, can the stems be said to be leafless, nor can they be compared to those of Ephedra. 



Tab. cm. L, juncea. Fig, 1, Flowerj Jig. 2, Floscule; Jig. 3, Anthers and stigmas ; Jig. 4, Achenium ; 

 Jig. 5, Portion of the hair of au achenium: — magnijied, 



2. L. minor ; caule ramosissimo obscure striato, foliis lincari-subuIatis brevibus, pappi 

 pilis sub-16 plumosis.— (Tab. CIII. ^ A. quoad fruct.) — Prsenanthes juncea. Douglas, 

 MSS. in Herb, Hart Soc. (non Purshii.) 



Hab. On gravelly or sandy banks of the Columbia, near Wallawallah, frequent. Douglas. — This is, 

 according to Mr. Douglas, 1-2 feet high. The specimens I possess scarcely exceed 10 inches, and the leaves 

 and flowers are smaller than those of the preceding species ; yet in every other respect the plants are so 

 similar that it is scarcely possible to distinguish them until the pappus be examined. This is totally different 

 from that of L. juncea; for whereas there it is composed of an infinity of very slender, tawny, and merely 

 scabrous hairs, here it consists of about 16 feathery hairs. 



TiR riTT. A. l^nwpr and nortion of a hair from the pappus of Zv<70t/e57m"a mi/jwr. 



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