lucr3oloqd:oru;o uosuedurocprc]J:Jedns " uEql erour JoJslseq lu3lJglnsu u" epr.lo:d pur:jar:c1 'l€sodslp iaqler eft suorlducsep crreue8 s.e11t,t1e11 slq le FI.Iel"u pellull rql Jo esn€coq 'dnol8 sdeq:a6 e.rouei xrs ts8uorup ssrcadsstt pelnqlJlsrp (9961) elll^le6 slq] Jo ]uetuleeJl r^rlrurlap lsel erll ul (8961 seleg) 383c"^l€l ,{lruq ern Jo a"e^le}{ equ} aql ur ecuellls sn4tuo1Eo14pelleJ-os eq] Jo srequreuruelpllsnv ere ,{pn1sslqt uI par3prsuoc"xel eqf uoplnpollul " """ " "" " . 0L2 oDuartwal ur sur,(uou,{5puE ssueN ol xepul L9z l'lucctsYll vgz seruereJeu " "" " " V9Z""" slueruc8pel.{\oultJv ............ .. .. ,92.. uorlrpadxgqUrC,se[C uro{ sueurrJads """" " " """ 292 ,{qdu:3oe3ofq4 " """" " "" 292 1es-tedsrq " " 09Z dlrl"nxes . 992 ,{Sotoqdrot ggz uorssncsrc ggz u€,rE xe surleH sflrrouorz srultuDlSDlduo etou V LlZ luelulee{ clluouoxEJ glz suorl"leprsuoJcrruouoxel " trc'-""""" ,{qderSo)3o1,{qd . 902 ,{Soloqdroln{e,rrleredruo3 . g0z. spoqtetr^{pu" slerrsl"l l -- Z0Z ,{JotsrHctruouoa€l I0z uorlcnPoJtul eBe4 slualuoJ rlenhr l r/r,rrrlr^ so(llo.)ou.,tuqrr,,^ perrLu{uou^s purr r.cn^r.r^reql .uo.rrpap.rrxe t' "Tl:"':j",'lii:? snituuou snrlrlDt8Dkf ruoz pu! .qlio uorr€zruolor puB uorrr.Ursra^rpr.qunj \rl?l lFs purrlul lo sulBrpu a$ 01 p tesDdsrp,{qtesl]dsrp,{q F}\oIol perrnrro uortpJrllsro^rpuo'tpJursro^rp FrtrurFItIur srrsrl araq,\\araq^\ ur3uo lr?ronrl p?q snue8 oqr lrql pizlsrqlodiq sr llrl passnasrpp.ssn.srp .tNatg DnDriALllDnu)riALll lo san.ds Jo susrueqJiulstusrueqriul psrlLpsl:)dslp eql uorrralas prlElp.Lu-roleurttod ol esuods3r ur pr^to^e sxq snu;8 cql ur ,{riorp }Eqt p3lsr3'lns sr lt r}lnrl1Jlrd lt Lul-r|V snqunlSotd eql puE l3r!u33 ul :r3^teft equl aqr Jo t?q! ot pri?tar pup pessnrsrp sr snu!8 aql Jo ,iiotoqdrotu 3^IllrrBdruo. eqj Prpr^ord sl rr)rrrarT lo sarredspur pxBl.lruiSir{ur ol ,i.:t p;rrilsnllr 3.rEsarreds pr.^:rs p.ssossrsr sntqs uortn^resuorsll V 'uollnqlrrsrp :el?t]dorddc ir.q^\ parerrpurere pouod ;uu3,l\ou pun ]Iqtq sll lpaqursep ittnj srso03d! qrej pcqrr:)s3p p\rl str pu? pilu.s.rd sr uorlprurssElr ru.uaBe.{ur ntiu V ?Ilrrlsnv ul]tsarr or rruepua qroq .rr qrtq,t rrrrrl) '{rolurit 'pu"tsueeno j pnB DtuEtll^I f.) ? pur ur:quoN 3ql pur xrplsnv urqsi/A ulor] D)strt tplt^ ? urirsri qtrou ]dto.tJs6uauDuDq)nq 7 :orutt tsrU aqt rol pequrs3p ert esoql lo rnol isrrrJd\ Z | \urltuor snurF rqf Fsr,\ar sr (llr^l:t,l vuwDltlaudpS snuoBoq1 ur po.eld flloturoJ s.Itcds tulpnl.ut IooH Dnua^q 6861) ILZ -t0Z {Dpue'I l(Z) e Ersr,nN (oe.^pt{ :aeore^p!{) l.oo]d DDua!$lI snue8 uerlerlsnv .q1Jo uoKl^ad S N lJsrlsqv .runuEqr.H l! l9 rrrrlsnV ur:ls3lA quad qlnos 1.orls riiosC UEIIEISnVur3lsalA JapuE'I's 'N 'yoop (aue,r.ptr41:oBerB^lBtrAI) npuahto? snue8uullur]snv aql Jo uols!^og (tg6t) l/Z-t0Z:(Z)9 elstfnN Z0Z NultsiaVol 5,No. 2 (1984) not presented features or for i:rropercircumscription of his taxa Speciesdescriptions were by Melville. Thi lick of effective keys togethor with the presencein Australia of several hitherto unrecognizedspecies has led to much conlusion in herbarium collections' The present revision is based on a reassessmentof morphological oharactels ol specles preuiouily consigned to the genera ltwrentia and Salenothqmnus. Despite considerable variation'in habii, trichome type, sexuality and fruit and seedmorphology, it is considered that the division betweel IL\\ren(:ia and Selenothumnuscan no longer be upheld and that the 12 speciesconcerned are best placed in a single genus. Although clearly delimitable groups e;erge, thesedo not correspond to preYiousgeneric concepts,nor does the evidence ieern strong enough to suppofl their recognition at generic level. A possible cxception Is L. berthae, a tptii"t to much at variance morphologically with those remaining in the genus that a str;ng case could be made for its segregation.This has been deferred pending further investigation ol the genera ol lhe Plagianthus aliance. Taxonomic History The gcnus lirwrencia was erected by Hooker (1840) to accommodate a single species, L. spi(.tta, specimensof which had been sent to him from Tasmania by Ronald Gunn. Hooker (1842) describeda secondspecies, l. glctmerata,sent to him from Western Australia by James Drummond. A third species,L. squamata, was added to the genus by Miquel (184s). Bentham(1862) united under PlagianthusJ. R. & G. Forst. (1776)non Jaub. & Spach (1845)species variously placed until that date in Asterotrichion Klotzsch, Blepharanthemum Klotzsch, H(tlothamr'r6 F. Muell., Hoheri.l A. Cunn, I'awrencia and Plagianthus.This action was followed by subsequentauthors, including Bentham in Bentham & Hooker (1862), Bentham(1863), Baker (1892),Schumann (1890), Dalla Torre & Harms (1900-7),Leme6 (1934) and Burbidge (1963). Several new speciesof Plagianthus sensu lato were described during this period. In January of 1909,O. Stapf exhibited specimensand lantern slidesof Plagtunthushelmsii to members of the Linnean Society of London pointing out that it appeared more natural to him to treat that speciestogether with P microphyllus ar'd P. squamotuJ as members of a distinct genus for which F. Mueller's name HalLtthomnus, orginally applied to P microphyllus, would have to stand (Anon. 1909).Amongst those pa icipating in the ensuing discussionwere E. G. Baker and T. A. Sprague. Sprague and Summerhayes(1926) examined the New Zealand representativesof Plagianthus sensu lato which they assignedto two genera, Plagianthus sensu stdcto and Hoheria, notingit passingthat the Australian speciesof ltwrenc:ia and Hqlothamnus should be excluded from Plagianthus. In the late 1930s, E. G. Baker prepared the draft for a paper which described three putative new speciesof Lawrencis and provided a partial key to the genus From his dralt it is clear that Baker intended to reinitate the gerruslawrenciz. It is wo hy of note that Plagianthu; berthae ariLdP. helmsiiwereexcluded from consideration,although the significance of this is not explained. Copies of his unpublished manuscript are held at BM and PERTH. Baker anrotated specimenshcld at BM, K and PERTH. In a more comprehensivestudy of the Plagianthus complex, Melville (1966) divided its speciesamongst six genera. In particular, speciesplaced by Bentham (1862) n Plagianthus sectron lr\urencia were now allocated to two separate genera, namely ltwrencia ser's]u stricto and Selenothamnus, founded, as Stapf had originally suggested, on Mueller's 'uorlelueserd crurouoxel IsruloJ sql s,,r,iolloJr{crq.,tt 3cuecgru8rs ,{J"uorlnlo^epu? cluouoxet JraqlJo uorssncslpplauo8 eql JoJpue oDuah$rJ Jo uoll€cUISSEIc Surnsueeql JoJ srs"q " epnord ereq poreplsuoc slre.t1pctSoloqdroru eq1 snue8 eql 1o sJeqtuetu[e 01 uouruoc su;e11edpcrSoloqdroru lurcgru8rs Jo uorleu€A Jo o?u€r otll uo 'a)uat$D1 poceld sr sseqdrug 3o ,{3o1oqd.touroql Jo tunocce olltsneqyo ue epr,ro:d o1 Surtrdruelleu?ql reql€J ,{8o1oqd;ouj1o stcedsea.Lrlereduoc qll,r\ peurecuocsr uoqros srql ,{Bo1oqdro141a,r.gu.reduro3 '(ssardur) ropu"'I ul puno; eq deur '8uuaql€E sepcqdnp elq€ll"^" Jo uolt"clpul uB qrl\ reqFSol Jo setep pu? selll"u,sroFeIIoJ 'sertrl"col qlr,,r\sueuroeds po,{orlssp aql 1e yo 1sqe,ltsueqerdruoc y lsrrelst ue fq pat"clpul eJB 'txel tueprcJesrql ur pello,rur 1ou selecrldnppetnqulsrp ,{ltuoceJ eql uI ereq,taqe sedf,1u,{sro '.{laleunpog sed,(lo$ fq reqlre peluesuda: er" pe^Io^ur suerurcedsed.{l eql II€ ?rg }q3n"c pue p€oJ eql Uel sel"ls auoq Jreql ol Fueleu ueol SuluJnter {cnJl el{t ueq,tr pedorlsep e:a,r reded srql ur patrc (gg) unueq:eg u"IueruseJ eq] pue ('IAIr'{) "uolcl1 Jo ulnlr"qreH 'suarutceds Fuorl"N eql qtoq ruo4'sedf,1 Sutpnlcut oql lle leq1 Uodal 01 3^eq ()11el33l I 'sasEcsnon8rqu? asr,\\Jeqlour ,(Iuo pelrc er? s-requnu leeqs ro relsr8er urnueqlaq :elqelIEAEeleql\ pellc sI uollcalloc Jo 3lup eql requnu qJolJallot e Jo ecuesqeeql uI suorl"ls l"lols€d ole s?u.lulot peue^ul e1autsur ue,lr3 'oasu3-tpt,nt sertrE)o-l IlnJ ur pelrJ eJe3J3q p3qucsop ,{l,]!,\eu setceds 1o suerurcedselq"llE^" II€ orcua,turry1o uorldoJxoeql ql1\[ sercedsqcu e 1o e8ue: eql lnoq8no:ql s3trsle suorl€lndod Jo uorlecol oql 1ur:ed ot ,{preruud pepualur eru luetutearl ctruouox?l SultrolloJ eq1 ul slsll polr?lep arou eq1 reded srqt Jo uolsnlcuoc eqt le tuJoJ pel"Ilelqqe ut pept,tord st ,{pn1s srql Io esrnoc eql ur po]"louue pu€ peulruexe suerutcedsunu"qreq Jo lsll alslduloc V 'r7rupurspl Jo )uJulteJl rlqerEdLuoJou :r JrJqf 'sop ',{rolur3J I qlnos .,nep.rog (1961) le8ntq a p]el3ld pue urequoN oqt roJ (l/61) eppueddrq3 '?uotcr^ roJ (0861) eloqelSnBeg'"llErlsnv urolseiN roJ (0861) pr€eg'erlertsnv qtnos roJ (6/6I) uouv 'pueysuaenf rcJ (ZL6I) uouy ,(lerueu 'elets qcee ut slsueloq ,{q peldope dlpreua8 suorsr,\rp-qnspcrqderSoe8 eql ol pu" sdeu eqt ot eJualeJet,{q pateclput 's,r\olloJ $ sercodsqr€o Jo uorlnqulsrp eql 1?ql luour}lrsJl clluouoxPJ oql uI el"ls lEql ()1 peuguoc sr sercedse ereq.trerprtsnv uralsoi6 Jo uorpefo.r4 eery pnbg Ieqlruez ueqrue'I " uo Jo erleJlsnv Jo uorFeford ea:y pnbg seuuog " uo pesoduuedns sor€nbs e3r8ep ouo ur ocuerrncco neqt SurpJoceJf,q peldutoc ore,t ,{lalltcedseJ8-E sd"l,1'lut selcedseqt [e Jo uorlnqrJlsrp oql pup I del^l ur paleJlsnllr olJuar,trDTJo o8uEr Jrqd€r8oo8 lelol tql 'red€d srql puo eql te pelrc sueulcedsrunueqJeq eql ur per\.resqouorl"ue,\ plol eql uodn peseq e.r?pelsrl slueueJnseelr'{ (8961) slnorlua3-I ,{q pozrJeururnsosoql elo,r peldope sa:npecord pu" spoqlou eqf €ll"r1snv urrlsal\A ur luesord '€ueqJol{ selJedsJo uorlE^Jesqoplou pu€ uorFelloc uo pu" qsIlIJg tuE^oler pue ueII"JtsnV Joleru eql ,4q peueol ro 1" pouruJ€xosuerurceds unrJ"qJaq elq"ln^" Il" ;o ,{3o1oqd:our ssol8errr Jo .{pnrs e uodn*-iffil"ff:Jllxt epeusuorsrcop clluouox"]