236 Mr. D. Don's Descriptions of new Genera and Species 



scales, and in the structure of its pappus. M. DeCandoUe's 

 description and figure of this plant above referred to, are very 

 faithful ; but both he and Professor Lagasca, in adopting the 

 name of Willdenow, who had referred it to Perdicium, were 

 evidently ignorant of its being the Chcetanthera serrata of Ruiz 

 and Pavon. 



BiCHENIA. 



Involucrum imbricatum. FloscuU radii labio exteriore multi- 

 nervio ! Pappi radiis triplici ordine dispositis, apice peni- 

 cillatis. 



Involucrum polyphyllum, inordinate imbricatum : squamis lan- 



ceolatis, acuminatis, adpressis ; intimis elongatis, radium 



sequantibus. Recejjtaculum planum, nudnm. FloscuU radii 



plurimi (15 — 18), ligulati, bilabiati, fceminei, stamihibus 



sterilibus ; labio exteriore amplo, cuneiformi, obtus^ tri- 



dentato, coriaceo, glabro, multi-(10 v. i5)nervio ; interiore 



exiguo, membranaceo, bipartito : segmentis lineari-filamen- 



tosis, spiraliter revolutis ; disci hermaphroditi, tubulato- 



bilabiati : labiis longitudine aequalibus ; exteriore ligulato, 



obtus^ trilobo ; interiore bipartito : segmentis linearibus, ob- 



tusis, erectis. Filametita linearia, complanata, nervo medio 



manifest^ subcarinata. Antherce appendiculA^ ligulata, mu- 



cronulat^, coriacea terminatae, basi bisetse : setis ramulosis, 



plumosis, extremitate simplici, elongate. Stigma clavatum, 



bilobura : lobis brevissimis, crassis, conniventi-applicatis, 



pruinosis. Achenia angusta, compresso-tetragona, undique 



copies^ papillosa. Pappus pilosus, subpersistens : radiis 



infequalibus, triplici ordine digestis, apice penicillatis, le- 



viter plumosis. 



Herb'A pereniiis, acaulis, caspitosa, land albd, villosci, molli, sicci- 



tate lutescente, omnino induta. Polia fert Pedicularium 



quarundam, numerosa, radicalia, petiolata, interrupt^ bipin- 



natifida, 



