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



become confluent. They occupy the centre of the lacinise, and, 

 unlike the other plants of this family, there are no vessels ter- 

 minating in, or branching off from the sinus. 



Tylloma. 



Involucrum imbricatum. Flosculi marginales unilabiati ! Pappus 

 capillaris : radiis simplici ordine dispositis. 



Involucrum ovatum, polyphyllum, multiplici ordine imbricatum : 

 squamis integerrimis, mucronulatis, laevibus, coriaceis, ad- 

 pressis ; interioribus oblongis, apice coloratis. Receptacu- 

 lum nudum. Flosculi marginales pauci, foeminei, unila- 

 biati, vix radiati, obtusfe tridentati ; disci hermaphroditi, 

 tubulosi, exti\s sericeo-villosi, limbo bilabiati : labiis abbre- 

 viatis ; exteriore obtus^ tridentato ; interiore bifido, lobis 

 lanceolatis, acutis, erectis. Stamina tubo infra medium in- 

 serta : Jilamenta angusta, complanata, glabra, apice atte- 

 nuata : anther cb in tubum coalitse, basi bisetae : setis longis, 

 ramulosis, subplumosis : appendicula terminalis lanceolato- 

 linearis, acuminata, cartilaginea, anthera ips4 brevior. 

 Stylus filiformis, glaber. Stigma clavatum, bilobum : lobis 

 abbreviatis, conniventibus, crassis, obtusis, pruinosis, mar- 

 gine incrassatis. ^c/jenfa trigona, papilloso-muricata. Pap- 

 pus capillaris, deciduus : radiis simplici ordine contigiiis, 

 subaequalibus, basi apiceque puberulis. 



Herba multicaulis, lanugine laxd parciiis instructa. Radix ramosa, 

 annua. Caudex brevissimus. Caules procumbentes, cylin- 

 dracei, pur pur ascent es, 2 — 4>-unciales. Folia alterna, subses- 

 silia, in apice ramulorum aggregata, cceterilm sparsa, cuneato- 

 lanceolatUj limbata, integerrima, complicata, Jlexuosa, vald^ 

 coriacea, colore glauco ccerulescentia, utrinque glandulis ma- 

 jusculis, pedicellatis, sparsis munita, subtus costd validd basi 

 valde dilatatd, hinc carinata, semuncialia ; ]\iniovQ, pracipue 



supra 



