X.—On Some Eurypterid Remains from the Upper Silurian Rocks of the Pentland Hills

Abstract

The Upper Silurian rocks of the Gutterford Burn, in the Pentland Hills, have for some time been known to contain Eurypterid remains, but the fossils procured from these beds—chiefly owing to the exertions of Mr Hardy of Bavelaw Castle, and Mr Henderson, late Curator of the Phrenological Museum—have never been submitted to a thorough examination. When, therefore, by the kind permission of Sir R Murdoch Smith, Director, and Dr E. H. Traquair, Keeper of the Natural History Collection in the Edinburgh Museum, I was given an opportunity of examining Mr Henderson's collection, which was acquired by the Museum some years since, I entered upon the work with the expectation of finding some new and interesting forms which would repay description. My expectations in this respect have been more than fulfilled, as the collection has yielded five undoubtedly new species, one of which I have made the type of a new genus. If to these one adds at least two other new species which are in the collection of Mr Hardy of Bavelaw, and which I hope to have the pleasure of examining and describing at some future time, one is justified, I think, in saying that the Gutterford Burn is unequalled among Eurypterid localities with regard to the variety of forms it has yielded. Unfortunately the bed which has yielded these specimens is limited in extent, and further work on it would entail quarrying operations on a somewhat extensive scale.

Redescription ofDrepanopterus pentlandicusLaurie, 1892, the earliest known mycteropoid (Chelicerata: Eurypterida) from the early Silurian (Llandovery) of the Pentland Hills, Scotland

“…The description of the Pentland Hills arthropod fauna in two seminal papers by Laurie (1892Laurie ( , 1899) marked a turning point in eurypterid research. The co-occurrence of so many species at a single locality makes it the most diverse eurypterid locality in the world (Plotnick 1999) while the style of preservation means that vast amounts of morphological detail can be observed, especially of the organisms' ventral surface.…”

“…Laurie's morphological descriptions were generally highly detailed and accurate; however it is only recently that they have been viewed in a context beyond their initial taxonomic assignments, which were somewhat constrained by the framework at the time. Waterston (1979) reviewed many of the stylonurine eurypterids, although it is only in recent years that there has been serious renewed interest in the Pentland fauna with the recognition of Bembicosoma pomphicus Laurie, 1899 as a synziphosurine (Anderson & Moore 2004) and Kiaeropterus cyclophthalmus (Laurie, 1892) as a member of the Stylonurina and not a Eurypterus as initially described. Reinvestigation of the various further Drepanopterus species described by Laurie (1899) revealed that the genus was polyphyletic and that 'Drepanopterus' bembycoides Laurie, 1899 and 'Drepanopterus' lobatus Laurie, 1899 were synonyms of 'Nanahughmilleria' conica Laurie, 1892 and belonged in a distinct genus closely related to members of the basal Eurypterina (Lamsdell 2011), while Drepanopterus pentlandicus Laurie, 1892 remained within the Stylonurina.…”

“…Redescription of Drepanopterus abonensis Simpson, 1951 from the Upper Devonian of Portishead, Somerset showed it to be a basal member of the predominantly Carboniferous-Permian sweep-feeding mycteropoids, a derived stylonurine clade marked by their bizarre morphology and generally large size (Lamsdell et al 2009). Comparison with Laurie's (1892Laurie's ( , 1899 published figures suggested that D. abonensis and D. pentlandicus were indeed congeneric, making the Llandovery D. pentlandicus the earliest mycteropoid. However, the temporal gap between the two species (some 54 million years) and the limitations inherent in studying the figures from Laurie's original works mean that restudy of D. pentlandicus is needed in order to confirm the monophyly of the genus.…”

The stratigraphy of the North Esk Inlier, Midlothian

“…brachiopods, crinoids, ostracods with bivalve molluscs and corals (Lamont 1954), the Reservoir Formation is poorly fossiliferous (see faunal lists in Mykura and Smith 1962). In its lower parts only fragments of Dictyocaris are found in any abundance; higher up, in the Gutterford Burn, occur the well known Eurypterid and Starfish Beds (Laurie 1893(Laurie , 1899Spencer 1914-40), but little else in the way of an in situ fauna. A sparse graptolitic fauna is also found at a few horizons (Mykura and Smith 1962).…”

Bembicosoma re-examined: a xiphosuran from the Silurian of the North Esk Inlier, Pentland Hills, Scotland

“…The importance of this area as a source of exceptional fossils has been recognised for over 150 years, since Maclaren (1839) published his account of the geology of Fife and the Lothians. This provided Malcolm Laurie with the fossils that he later described in great anatomical detail (Laurie 1892(Laurie , 1899. This provided Malcolm Laurie with the fossils that he later described in great anatomical detail (Laurie 1892(Laurie , 1899.…”