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Review of Palaeobotany and Palynology 116 -2001) 123±158 www.elsevier.com/locate/revpalbo Rotted wood±alga±fungus: the history and life of Prototaxites Dawson 1859 Francis M. Hueber* Department of Paleobiology, MRC-121, Smithsonian Institution, Washington, DC 20560-0121, USA Abstract The Devonian ¯ora discovered and collected by W.E. Logan in 1843 remained unstudied until 1855 at which time the collections were offered to J.W. Dawson. His attention was immediately drawn to a single large specimen in the collections, which he identi®ed and described as partially rotted wood of a conifer -Dawson, 1857). He proposed the name Prototaxites -Dawson, 1859) thereby expressing his concept of the genus. That concept remained unchallenged until Carruthers -1872) heatedly ridiculed both the name and the author and illegitimately substituted the name Nematophycus. His subjective opinion was that the fossil represented a fragment of a very large alga, like Lessonia. His classi®cation, challenged only once -Church, 1919), persisted in all subsequent reports. Dawson remained adamant in his de®nition of Prototaxites until he illegitimately substituted the name Nematophyton for Prototaxites -Dawson, 1888) and denied -Dawson, in Penhallow, 1889) that he had ever classed the genus with the conifers. The names Nematophycus and Nematophyton are later synonyms of Prototaxites and, although inappropriate in connotation, Prototaxites is nomenclaturally valid. No undoubted original nor associated specimens are available for choice of a lectotype. This report has a triple purpose: -1) to name, as neotype, a recognizable specimen collected by Dawson for which the locality and stratigraphic data are known, -2) to redescribe the genus as structurally composed of three interactive forms of hyphae, i.e. large thin-walled, septate, branching, generative hyphae; large thick-walled, non-septate, skeletal hyphae; and small thin-walled, septate, branching, binding hyphae, which combine to form a gigantic, phototropic, amphigenous, perennial sporophore with saprobic nutrition, and -3) to classify it in the Kingdom Fungi. Generic synonymy with Prototaxites is proposed for Nematophycus -Carruthers, 1872). q 2001 Elsevier Science B.V. All rights reserved. Keywords: Prototaxites; Fungi; Devonian; Canada; neotype; paleoecology 1. Introduction anatomy of other specimens collected later by Dawson -1858). Microscopical examinations of Among the fossil plants that were collected by W.E. ground thin-sections concluded that all of the speci- Logan along the shores of Gaspe Bay -1843), the most mens were silici®ed, partially rotted wood, as indi- enigmatic specimen resembled a fragment of a small cated by the very loose organization of the tissues tree. That resemblance seemed to have in¯uenced and the presence of an entangled meshwork resem- subsequent interpretations of the permineralized anat- bling fungal mycelia. The wood was not so rotted to omy of the specimen -Dawson, 1857) as well as the preclude naming the species Prototaxites logani and classifying it with the conifers, particularly among the Taxineae -Dawson, 1859). The etymology of the * Fax: 11-202-786-2832. generic name indicated his interpretation, and for E-mail address: [email protected] -F.M. Hueber). 29 years, Dawson, in his several papers -Dawson, 0034-6667/01/$ - see front matter q 2001 Elsevier Science B.V. All rights reserved. PII: S0034-6667-01)00058-6 124 F.M. Hueber / Review of Palaeobotany and Palynology 116 22001) 123±158 1859±1882b and 1888) dogmatically repeated and p. 62, August 14±17) he commented on collecting supported his conclusions. fossil plant remains at a site named earlier by Bay®eld Carruthers -1872), in the meantime, was the ®rst to -1837) as Cape BreÂhaut. At the time of Logan's visit, change the concept of Prototaxites by disclaiming any the local ®shermen referred to the site as Seal Cove, relationship of the genus with the conifers. He by which name it is known today -Fig. 1). Logan, in proposed an illegitimate substitution of the name apparent deference to Bay®eld, labeled his collection Nematophycus for Prototaxites; formally classed it site as Cape BreÂhaut. That collection and all of the with the Codiaceae among the green algae; informally other collections he had made during his survey compared it with Lessonia among the brown algae; received no attention until he offered them to J.W. and set into motion the concept that the genus was a Dawson for study in 1855 -Dawson in Penhallow, marine alga. That concept has not been rejected in any 1889). A particular specimen in the collections descriptive papers since the date of his publication. aroused Dawson's curiosity as it appeared to be fossi- New species have proliferated. lized wood. Thin-sections were prepared and Dawson The purpose of this report does not include a syno- interpreted and described the specimen as partially nymy of all of the species, even though years of perso- rotted wood of a tree closely related to conifers nal research have gone into the study of Prototaxites -Dawson, 1857). He did not formally propose a and all of its species based on available, original mate- name for the fossil but did cite the source of the speci- rial. On the subject of original material, I have found men as Cape Brachaut -sic). The citation was meant to that no undoubted original specimens studied by read Cape BreÂhaut, and the spelling was corrected in Dawson -1857, 1859, 1871) are extant. There is no his subsequent papers. His report established the site nomenifer, nor are there specimens from which a from which the ®rst specimen of the unusual fossil lectotype might be named. Locality and stratigraphic was obtained. The site is in the Battery Point Forma- data are available for the specimen used by Penhallow tion, early Emsian of the Devonian section, in Gaspe -1889) in his emended diagnosis of ªNematophytonº± Bay. Prototaxites. The specimen is in the collections of the Enthused by the variety and apparent abundance of Peter Redpath Museum, Montreal, Quebec, Canada fossil plant material in Logan's collections, Dawson and is designated the neotype of Prototaxites. A frag- journeyed to Gaspe -Dawson, 1858) to observe the ment of the specimen in the Paleobotanical Collec- occurrences of the fossils as Logan had described tions of the United States National Museum, them. He collected specimens, including more of the Washington, DC is used to emend the genus and to curious wood, and published his ®rst descriptions of establish its classi®cation with the Fungi. some of the elements in the fossil ¯ora -1859). He used Logan's original specimen and those he had collected himself to formally describe and propose 2. Brief history the name Prototaxites for the `wood'. The etymology of the name clearly indicated his interpretation of the W.E. Logan was the ®rst person to collect and af®nities of the genus with the Taxineae and particu- document the occurrences of fossil plants in the larly with the Recent genus Taxus. He may have had well-exposed sections of Devonian strata along the other thoughts about the identity of the fossil as shores of Gaspe Bay, Quebec, Canada. He accom- suggested by his sketches of microscopic details of plished this in the summer of 1843 during his mapping Prototaxites and Taxus baccata which were found and exploration of the Gaspe Peninsula for coal and among his collections. In his typically bold hand he other mineral resources. In his ®eld note book -1843, wrote ªLike mycelium of fungusº alongside the Fig. 1. Geographical locations of collection sites, Gaspe Bay, Quebec, Canada. -A) Seal Cove, where the ®rst specimen of Prototaxites was collected among other fossils by W.E. Logan during his mapping of the sections east and west of Seal Cove, 18±21, August 1843; Field Notebook, pp. 62±64. -B) Petit Gaspe -L. GaspeÂ), site of collection of ªSpecimen No. 5º by J.W. Dawson, 16±17 August, 1869; Field Notebook 1, pp. 31±32. -C) Geological Survey of Canada Locality #5388, specimen collected by D.C. McGregor, 15 May, 1959; Field #59-6, Notebook 1, p. 12. -D) Collection site of specimen of Prototaxites with vascular plant inclusions W.E. Stein, Jr. Locality #91-13, July, 1991. F.M. Hueber / Review of Palaeobotany and Palynology 116 22001) 123±158 125 126 F.M. Hueber / Review of Palaeobotany and Palynology 116 22001) 123±158 F.M. Hueber / Review of Palaeobotany and Palynology 116 22001) 123±158 127 genus have been lost or are inextricably mixed with later collections. These circumstances preclude the selection of a specimen as a lectotype from among the early collections. Dawson spent time, beginning July 22, 1869 -Dawson, Field Note Books #1 and #2), investigating the Devonian strata along the north and south shores of Gaspe Bay. He found occurrences of Prototaxites along both shores in which the `trunks' were still embedded in sandstone matrices and associated with other plant remains, particularly with Psilophyton. Each discovery supported his belief that the genus was terrestrial and indeed a large tree. Sketches and subsequent illustrations -Figs. 4a±c, 5a,b and 6a,b), with commentaries in his ®eld note books -Dawson, 1869a,b; 1881a,b; 1882a,b), re¯ected the increasing con®dence he held in his classi®cation of the genus. His commentaries and notation of dates have helped in establishing precise localities for some of the genera he later described, however, in many cases, the locality data accompanying his collections are given simply as Gaspe without stratigraphic control. At one point in his writings, he commented on collect- ing fragments of two large logs of Prototaxites -Dawson 1869a,b); one was three feet -0.914 m) the other two feet -0.606 m) in diameter. The latter speci- men was illustrated -Dawson, 1871, p. 17) from the sketch in his ®eld note book -Dawson, 1869a, p.

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