PRINCIPES IVol. lI FossilPalms JosepnA. Ture, M. D. Living palms are familiar plants to oryas (4, p. 172) mentionsthat the dis- "one all who grow them and are a character- covery was of the most significant istic feature of many parts of the trop- finds in recent times" although with in- ics. That palms have a long history in complete evidence it should be classi- time is not always recognized.It is the fied only as palm-like. Ladd and Brown object of this article to illustrate some also illustrated in color the cross-sec- o{ the fossil palms found in the United tion of a fossil palm trunk of a later States, correlating structure of stems, era found on Antigua in the West roots, and leaves with those seen in Indies. It has a light yellow-brown color living palms, the anatomy of which has similar to much of the fossil palm wood beenreviewed and evaluatedby Tomlin- found in Southern California. son in his volume on Palmae in Anato- Arnold (7, p. 341) placesmost of the my of the Monocotyledons(L). fossil palms in North America along Palms first definitely appearedin the with rocks of the Eocene epoch (36'58 Upper Cretaceous rocks, some 63-90 million years ago). There was a shi{t' million years ago by the geologic time ing or migration of palms southward scaleof Kulp (2). A fossil which has due to climatic changes at the end of been called Palmoxylon clillwoodensis the Eocene which continued into the dating from that period has been found Pliocene(I-13 million yearsago). Thus in the Magothy formation of New Jer- the occunence of palms in the fossil sey wheretoday no palm lives (3). De- record has served more or less as an Ievoryas (4, p. 173) mentions that indicator of the prevailing climate of palm-like leaf impressionsfrom France the past. No6 (B), La Motte (9) and (the Propalmophyllum of Lignier) were Mahabal6 (10) give many references reported in 1907 as dating from the Ju- on {ossil palms. rassic period ( 135-IBI million years There are several imPortant areas ago). If truly a palm, this stands as {rom which material of fossil palms has evidencefor the presenceof flowering been obtained. One of the most fam' plants at that early date. However, go- ous is the extensive region along the ing back still further, the discovery of coastal plain of the United States bor' a palm-like leaf imprint in sandstone dering the Gulf of Mexico, where rocks was reported and illustrated in color containing what is known as the Wil- (5) by Ladd and Brown and by Brown cox flora were laid down in lower (6) Triassicperiod (181-230 from the Eocene times. These beds contained A million years ago). This ancient fossil many fossils including Chamaedorea' leaf was found by Dr. G. Edward Lewis lt like species.At about the same time, near Placerville,Colorado, in the vicin- existedin northern New ity of the San Miguel River. Several the Raton flora months later, Dr. Brown and Dr. Lewis Mexico.and southernColorado. Knowl' explored the area where the first im- ton (11, p. IB0) includesa photograph print had been found. Six more im- of a leaf impressiono{ a Sobal-likepalm prints were uncovered and taken back from this flora. From a succeeding to the Smithsonian Institution. Delev- middle Eocene flora, the Claiborne r9671 TUTA: FOSSIL PALMS 55 which extendedfrom Alabamato Texas, in time, from the upper Eocene Berry (12, p. 5I) described several Jackson flora of Texas, fossil fruits o{ palms basedon leaf structure-one sug- a date-like palm were found. Chaney gestive ol Thrinax, and two feather- (13, p. 1I) publisheda photographof leaved speciescalled Baetrites and.Geo- a large bed composedof layers of fossil nomites from their resemblanceto mod- palm leaves from the Clarno shale of ern Bactris and, Geonoma. Still later Oregon, also of Eoceneage. Most of GElLOGICTIME SCATE 'j;:"[H:t"(') PERIOD POSITION OF FOSSIL PALMS bEGINNING & DTJR,ATION IN CEOIOGIC TIME SCALE ;ND OF PERIOD *PALMS IN AUITIORIS COLLECTION RECENT 0 - 0.01 0.01. I lo onn u PLEISIIOCENE- a 0.0r.- r.ot L aER(), TURIDA PLIOCENE IRICARDO BEDS upPer 1-13 L2 (I.AST CTIANCECANYON) CALIF(N,NIA :oPIAH COI'NTY, MIS$SSIPPI IROSAIT{OND,CALIF. (NEAR MOHAVE) MIOCENE IAPAIT (TERTIARY) EPOCH NOT KNOL'N uPper IBARSTOC BEDS (MULE CANYON) CALIF. mlddle L3-25 L2 KTEHACHAPI, CALIF. (HORSE CANYON) lower TIAGRANGE, L FAYETTE COUNTY, TEXAS OLIGOCENE 25-36 t1 INTIGUA, WEST'INDIES ? OLIGOCENE fr SUB-DTVISTON NOT I(NOT.'N EOCENE 36-58 22 TFARSON, [tYO,tINc (EDEN-VALLEY) ll TNEPHI,, H UTAH : kSIERRA COI'NTY, NEtr MEXICO E- upPer io-+s 9 :LARNO, OREGON, FOSSIL LEAVES 01 IACKSON.FLORA - GULF COAST REGION ]RAZOS CO. TEXAS. NIPA.LIKE FRUITS T{ nlddle 45-52 7 - E{ :I,AIBORNE.FLORA GULF COAST REGION TATON.FIORA NORTHERNNEW MEXICO lower 52-58 6 IILCOX FLORA GI'LF COAST REGION IIPA-LIKE FRUITS GRANADACO. MISS. WORTH CAROLINA PALEOCENE ,7 -63 5 IRAZIL. NIPA-LIKE FOSSIL FRUITS CRETACEOUS OSSIL PAII{S FIRST APPEAR IN UPPER-li..l uPPer 63-90 27 LEI. _IERIgD (MAcoruy rmuruoH) Iower 90 - 1.35 45 IT'RONIAN OF FNAN.:N JI'RASSIC - r35 - 181. 46 ,AW-LIKE I.EAF IMPRINTS N,OPALMOPHYLLIJIT{OF LICNIER (FRAIICE) TRIASSIC LEl - 230 49 IAIX.LIKE LEAF IMPRINTS (COIORADO'- PER},TIAN l3o - zao 50 PENNSYLVANIAN 180 - 320 t8 MISSISSIPPIAN t20 - 345 25 Jl DEVONIAN ,45 - t+Os 60 SILURIAN lO5 - 425 20 NO EVIDENCE OF pAL!,rS u ORDOVICIAN ;25 - 500 75 OR CAI{BRIAN '00 - 500 100 PAI.Iq.LIKE STRUCTT'RES INCLUDES THE BEIOII THE TRIASSIC PERIOD OLDEST BASEMENT ROCKS FROM THE 600 - 3600+ 3000+ TIME OF M,IGIN OF THE EARTH UP TO THE LOWERCAI{BRIA PERIOD ! PRINCIPES lVol. 1r the {ossil palms b{ Wyoming occur in Eocene age have also been found in rocks o{ the same age. Belgium, Borneo, France, India and Fossil palms in Texas are found in Russia. Some of these structures rocks from both the Miocene and have also been found in beds of Eocene epochs, those from Fayette Miocene age in India. Fossil pollen County being of Miocene age. In Cali- grains have beenreported frorn Borneo fornia, the Tehachapi {lora of the pres- in beds of Cretaceousage. In the Uni' ent western Mohave Desert region was ted States Nypa-like {ossil fruits have laid down in the Middle Miocene(about been{ound (Berry 19. p. 176) in the 18 million yearsago) while the Barstow Wilcox (Eocene)flora, Granadaforma- beds, which include the Mule Canyon tion, Granada Count-y, Mississippi. t i area north of Yermo, are of upper Mio- From Texas Berry (12, p. 150) re- q ceneage (I5 million yearsago) and the ported similar fruits found in the Eo- Ricardo beds of Southern California, cene Fayette{onnation near Wellborn. which occur in the Last ChanceCanyon Brazos County. Also {rom the Paleo- area, are o{ lower Plioceneage. Axelrod cene of Brazil. {o,ssilfruits oI lYypa (14) describedfossil palms of Plio- havebeen reported by Dolianiti (20 ) in cend age from Palmdale,California. An 1955. These structures can dri{t {or imprint of a Sobal-likeleaf with a costa- long distanceswith the oceancurrents. palmate blade was revealed during the The oceanicpaths of migration are dis- processo{ road building near Castaicin cussedby Corner (21, pp. 249-252\. Los Angeles County and is illustrated He also suggeststhe possibilit,vthat the by Hertrich (15, p.4). From Japanon .Nypo- like fruits found in southenr the islands of Hokkaido and Kyushu. U.S.A. may be from tropical Anrerican Kryshtofovich (16) has describedSa- palms other than l{ypa. bal-like palm leaf impressions. In Eu- One of the most inforrnative de- rope, during the Focene epoch, Sabal- scriptionsof how plants becarrefossils like palms grew in England. France and is givenby Arnold (7. p. 14-40).Com- southern Russia and also appear in the pressions,casts and petrifications(per- Pliocene rocks of the Rhone Valley. mineralization)are the most inrportant' Eocenebeds of England occur in two methods by which fossilization is e{- separatebasins, the Hampshire and the fected.O{ the monocotyledonousplant London. Fossil fruits o{ the tropical forms, the petri{ied (silicifiedI palnrs palm Nypa (Nipa) have been found in are among the best preserved.Manl' the old delta mud or clay which lies be- factors are involvedin the petrification low London. It is also exposedin the process.One importantfactor for sel- clif{s of eastern Kent County and the ting the stage for petrification is the Isle of Sheppeylocated at the mouth of rapid submergenceof the trunk and the Thames River. Reid and Chandler roots in a body of water where ox1'gen (17) and Chandler(18) have made ex- is absent. Another important factor is tensive studies on the flora of the Lon- deposition in the water of finely di- don clay in which fossil /Vypo struc- vided sedimendssuch as clay. nrud" tures have been ,found. Geologically sand and volcanicash. this important palm has existed since The complexpetrification process has the Cretaceousperiod. At the present been studiedby Arnold (22), Darrah time lVypa is restricted to parts of (23) and Barghoorn (24, 25). Ther' southeastAsia and some of the South have produced much evidenceindicat- Pacific Islands. Fossil Nvpa fruits o{ ing that the {undamentalbasic process TUTA: FOSSIL PALNIS 1. Fossil palm, Tehachapi,Kern Co., Calif. Photograph enlarged3 X. Trro x-vlemvessels- occasionallythree, in each vascularbundle stand out like ink dots. \\'ith the use o{ a 4X or 10X lens some bundlesshow groups of phloem structuresbetleen the r,vlem vesselsand the "cap", large fibrous bundle sheath also .agatizedsepta diliding the palm structure into lslan d s.