STATE OF ILLINOIS AULAI E. S'TEVENSON, Govei of- DEPARTMENT OF REGISTRATION AND EDUCATION NOBLE J. PUFFER, Director DIVISION OF THE STATE GEOLOGICAL SURVEY M. M. LEIGI-IT'ON, CIzief URBAN-4 REPORT OF INVESTIGATlONS-NO. 132 PTERIDOSPERIV~MALE FRUCTIFICATIONS : AMERICAN SPECIES OF DOLEROTHECA, 1VJTI-I NOTES REGARDING CERTAIN ALLIED I'ORMS JAMES M. SCHOPF Rmw~-nsnFROM THE JOURNAL OF PALEONTOLOGY Vor,. 22, No. 6, NOVEMBEI~,1948 PRINTED BY AUTHORITY OF THE STATE OF ILLINOIS URBANA, ILLINOIS 1949 STATE OF ILLINOIS RON. ADLAI E. STEVENSON, Govevnov DEPARTMENT OF REGISTRATION AND EDUCATION HON. NOBLE J. PUFFER, Directov BOARD OF NATURAL RESOURCES AND CONSERVATION i- : , . lilga HON. NOBLE J. PUFFER, Cltail-mars W. H. NEWHOUSE, Pi<.D., Gmlogy ROGER ADAMS, Pxx.D., D.Sc., Chemistry LOUIS R. HOWSON, C.E., Enginccrirtg A. E. EMERSON, PILD., Bwlogy LEWIS If. TIFFANY, Pzr.D., Forestry GEORGE D. STODDARD, PII.~.,LITT.D., LLD., L.H.D. Prrs[dent of the University of Illinois GEOLOGICAL SURVEY DIVISION M. Ad. LEIGHTOM, Pn.D., Ckief SCIENTIFIC AND TECHNICAL STAFF OF THE STATE GEOLOGICAL SURVEY DIVISTON 100 Natzwal Resozarces Building, Urba~za &I. M. LEIGNTON, PI~.D.,Chief ENID TOLVNLEY, M.S., Assistaut to tlzc Clzief VELDAA. MILLARD,Ji~.izior Asst, to the Cliicf HELENE. MCMORRIS,Secretam to tlte Chef BERENICEREED, Sztper~li.so~,jlfccle~tical Assistaizt GEOLOGICAL RESOURCES GEOCIIEMTSTRY FRANKIi. REED,PII.D., Clzief Clzemist (on leave) ARTIIURBEVAX, PJI. D., I).Sc., Pri11cifial Geologist GRACEC. JOTINSON,13. S., Resefl~cizAssistant Cod Cool G. H. CADY,~'H.D., Se1ziol' Geoloqi~fand Head C. R. Yoill.:. P~r.f) Clzer~tistand Head R J. HELFINSTIKERLS., Mec~~a;~icalE?tgineer iiu~rlC. IVILD~AN: M.S., Assistant Chelrzist R~BERT M. KOSAN~E M A. Associate Geolog~st \VM. F. L~RANGER,E.A., Reseal-ch Assista~zt JOHNA. HARRISOX,~I.s.', ~ssistalztGeologist JACKA. SIMON,M.S Asslsta~ttGeologist (on leave) RAYMONDSIEVER, M:k., Asszstn$zt Geologist MARYE. BARNESM.S.. A~szstu~ttGeologist J. S. ~IACIIIX,PJI.~)., Chemisl and Head MARGARETPARK&, B.S., A.ssista+zt Geologist TIN Boo YEE, M.S., Assistant Chemist KENNETHCLEGG, Tc~I~~~rcal Assistalzt I'AULEN~EKU AN, B.A., Rescc~rrlzAssistarzt 1;luor.rpar Oil and Gas G. C. FINGER,1'11. I) Chewist and Head 4. H. BELL,PII.D., Ge010gi.st n~ldHead Ho~srG SCIINEIDER" B S Special Assistant Cke~~zist FREDERICKSQUIRES, A.B., B.S., Petroleunl Elrgi~teer- WILLIA; FREDERICK' BUT;, R.S., Special Researclz ])AVID H. SWANNPH.D., Geologzst Asszstant V~RGINIAI<LI NE,'PII.D Associate Geologist RICHARDBLOUGII, B.A., Research Asststalzt WAYNEF. MEENTS,A&stavt Geologist ROBERTE. OESTERLING,R.A., Sfiecial Research RIC!IARD J. CASSIN,B.S., Assistawt PetvoIe~~~iEll- Assistant g'lneeie J.zhr~sL. FINNERTY,B.S., Sl~eciaIResearch Assistant LESTERW. CLUTTERB.S. Researclz Assistant Nnxcu CASSIN,B.s.,' ~eseirclzAssistant Clz PIIIicoI Efjgis1~erig1.q Id. \Ir. JACK~IIN, M.S.E., Cl~e~iiz~alEagi~zeer and Head J. E. L.~M.~R,B.S., Geologist md Head 3'. 1%' HENLINLM.S., CIZCI~Z~CC~IEltgineer JIOBERTM GHOGANPIT. D., Geologist B. J. 'GREEN WOO;, B. S. Meclzanical E~zgmeer RAYMONDS. SIIROD;, B.S., Assistant Geologist JAMESC. RICCULLOUGII~ Research Associate S-rcry n17d Specilvgraplzy Clay Resources adClay ikli~ze~alTech~zology W. F. BRADLEY,PII.~., Cherriist aud Head RALPH E. GRIM P11.D Petrogt-aplwr and Head WILLIAMA. LVLITE &i?~.Associnte Geologist HERBERTD. GLASS,MA, kssocinte Geologist KENNETIIB. TS~UBISON,1'11.0., PIzy~icist Groundwater Geology and Geophysical R. J. PIERSOL,I'II.T~., Physicist Enzeritus Explomfion CARLA. BAYS,PKD., Geologist curd Engi~zecf;and '0. W. REES, P11.U C'he~?iistand Head Head IJ.D. MCVICKER,B.'s., CIzentist ROBERTR. STORMA.B., Associate Geologist HOWARDS CLARK A.B Assoczate Chemist MERLYN B. BUI~LE, 1I.S. Associnte Geologist EMILI 1). 'PIEIIRO~,&I.$., Assistant Chemist M. W,PULLEN, JR., RLS' Asxocrnte Geologi~t ELIZABETHBARTZ, A.B., Research Assistant JOITN W. FOSTER,R.A., ';lsscstn~tt Geologist T~ONALD RUSSELLHILL, B. S., Research Assistalzt RICIIARDF. 171s1~E~h1.S Ass~sta~ztGeologist RUTH E. KOSKI, B.S., Reseai,ch Assistant MARGARETJ. CASTL~ As&tant Geologzc Drafts~zall ANNABELLEG. ELLIOTT,B. S., Techlzical Assistant ROBERTKNODLE, &I.s'., Assistant Geologist MINERAL ECONOMICS E~gineeringGeology and Topograplaic Milflpiug \V. H. VO~KUILPl1.D Mineral Eco~zornist GEORGEE. EKBLAW.PH.~)., Geologist a~tdHead W L. Bvsclr '~esear&Associate NINA I~AMRICI;,A.M., Assistant Mil~eralEcolzofi~ist Areal Geology and Paleon,tology ETJIELM. KING, Research Assistant H. B. WILLMAN,PH.D., Geologist and Head EDUCATIONAL EXTENSION HEINZA. LOWENSTAM,PII.D., Geologist (on leave) GILBERT 0. RAASCII,PII.D., Associate Geologist J. S. TEMPLETON,PII. I)., Geologi~t i~tClzarge I)OROTRYRANNEY, B.S., Tcch~iicalAssista~zt S~dmwface Geology L. E. WORKMAN,M.S., Geologist a?$d Head LIBRARY ELWOODATITERTON, PII.D., Assocaate Geologist ANNEE. KOYANDA,B.S., B.L.S Librarian PAUL HERBERTJR., B.S., Associate Geologist RUBYD. FREON, Technical ~sssstant DOXALDSAXBY,' M.S., Assistant Geologist ROBERTC. MCDONALD,B.S., Research Assista~qt PUBLICATIONS LOIS TITUS, B.S., Researclz Assistant DOROTSLYE. ROSE B.S. Tech&al Editor 34. ELIZABET~~ST~AKS, B.s., Assistant Editor Mi~zeg~alResource Records MEREDITHM. CALKINS,Geologic Draftsma~z VIVIAN ORD DON Head ARDISD. PYE, Asristant G~ologicDraftsnzan HARRIETC. DA~IELS,B.A., Trclznicnl Assista~zt WAYNEW. NOFFTZ,Tech?zical Assistant DOROTHYGone, B.S., Teclznical Assistaqzt LESLIE 1). VAUGIIAN,Associate Photographer DOROTHYA. FOUTCH,Teclzlzical Assistant EEULAIIM. UNFER,Tech~iical Assistant ZORAM. KAYINSKY, B.E., Teclz~~ictrlAssistrrlrt +tcti~igCl~icf Chemist in interim of ahsence of ELENEROBERTS, Techn~cul Assistnnt Cliief Chemist. Consultants: Geology GEORGEW. WIIITE PH.D University of Illinois eram mi is RALPII K. HURSJI' B.S ?.JniveYsity of Illinois ~echar~ihEnginee~i+zg SE~CIII KONZO M.S University of Illi~~ois Topographic Mapping in Cooperation ;it11 the United htates'beological Survey. January 10, 1949 PTERIDOSPERM MALE FRUCTIFICATIONS : AMERICAN SPECIES OF DOLEROTHECA, WITH NOTES REGARDING CERTAIN ALLIED FORMS JAMES M. SCHOPF U. S. Geological Survey, Washington, D. C. ABSTRACT-Dolerothecaincludes a group of pteridosperms (Medullosaceae) char- acterized by very large and unusual pollen-bearing organs. Their botanical per- tinence to plant microfossil studies and to phyletic theories, as well as their rarity in good preservation, lends considerable interest to these fossils. The morphology of the polleniferous organs, or male fructifications, is reviewed preliminary to taxonomic treatment of the new American material. Three new species are described in considerable detail both as to general external form and internal organization-a result possible only because of preservation in the limestone concretions in coal beds known as coal balls. The species of Dolerotheca are assembled in a new sub-tribe called the Dolerothecinae. The evidence for relating these forms with other coal- ball fossils known as Myeloxylon, and, in turn, with Medullosa, is discussed with par- ticular reference to one species where the peduncular organ of attachment seems to be preserved. Notes are also included regarding a specimen of Dolerotheca pre- served in surface imprint in an ironstone concretion, and regarding the allied Whit- tleseyinean group classed as Codonotheca. The relationships and comparative anatomy of Dolerotheca with other pteridosperm groups that present homologous features are discussed and a tentative evolutionary interpretation presented. Hetero- theca of the Lower Carboniferous appears to represent a plausible ancestral type, combining features of both the lyginopterid and medullosan lines of descent. The morphology of Dolerotheca suggests, however, that evolutionary modification has been by elaboration and septation of a single telomic structure rather than by adna- tion and concrescence of many. INTRODUCTION that differ radically from organs known in HE male fructifications of pteridosperms ferns. A more complete understanding of the are less well understood than most of characteristics and the nature of the diver- the other organs pertaining to this large sity of male fructifications in pteridosperms group of ancient plants. The fact that a will have important influence on ideas of considerable number of the Paleozoic fern- phylogeny and relationship among this like plants bore seeds and hence were not large, chiefly Paleozoic, plant alliance. true ferns, in spite of their highly dissected Among the pteridosperms the plants or pinnatifid leaves, became established classified as Dolerothecn display conspicuous about 45 years ago. Since then a number of differences with regard to their male fruc- pteridosperm seed types have become well tifications. Such fructifications of Dolerotheca known; on the other hand an equivalent have not been comnlonly reported, and up amount of information has not been ob- to the time specimens here described were tained about the male fructifications de- discovered, only a single fragment was spite the fact they must have been numer- known which showed well preserved tissue ous. Some of the first recognized pterido- structures. A few surface impressions and sperms seemed to have male fructifications coalified compressions of sirnilar fructi- resembling the synangia of ferns. These fications have been recognized, but these are organs were presumed to be conservative difficult to interpret and naturally afforded and little modified in the evolutionary tran- much less conclusive information about sition