As part of the preparation for reviewing the Paleozoic rhynchonellids for the revised brachiopod treatise, one of us (NMS) requested help from Dr. Howard Brunton, of the Natural History Museum (British Museum, London) in obtaining type material of Propriopugnus pugnus (Martin) to further investigate the internal features. Dr. Brunton kindly sent a Natural History Museum specimen that he considers to be close to the lectotype. This specimen has been photographed and sectioned, and it is described below.

Preliminary experiments with a confocal microscope (Sarastro 2000®) demonstrate its value in micropaleontology for photography and three-dimensional morphometric studies. High-quality images of objects in the size range of 100 to 2,000 μm can be obtained without application of nonremovable coating. Images can easily be electronically converted to stereopairs or displayed as single images. Images are in focus throughout and are superior to light photographs. Numerical data (x, y, and z coordinates) in almost any desired amount can be extracted from enough points on the visible surface to provide for the construction of a detailed topographic map of the surface. All of this can be done without manipulating the specimen once it has been mounted.

A hand-specimen, bedding-plane sample of limestone (wackestone) from the Upper Ordovician Waynesville Formation has numerous brachiopod specimens (at least 60) exposed on its surface (Figure 1). The brachiopods have been identified as members of the atrypid species Zygospira modesta (Say in Hall) 1847 (the type species of the genus Zygospira Hall, 1862) and are concentrated in an area measuring approximately 9 cm x 2 cm. A wide range of specimen sizes from juvenile to adult are present and are believed to represent a brachiopod life-assemblage (Figure 2).

In 1994 an extensive collection of mainly Carboniferous conodonts was transferred from the Department of Geology, University of Southampton, England, to The Natural History Museum, London, on the retirement of R. L. Austin. The collection consists of approximately 2,000 slides of type/figured specimens and picked residue slides, which complement material previously deposited at The Natural History Museum, London. The following is a very brief resumé of figured material in the collection.

Various workers have assigned Atrypa acutiplicata Conrad, 1841, to a number of leptocoeliid genera. Restudy of specimens previously examined by Boucot and Rehmer (1977) as part of a study of the community paleoecology of brachiopods of the Emsian and Eifelian strata of eastern North America has shown that A. acutiplicata does not belong to any existing genus of leptocoeliid. Therefore, the new genus Atlanticocoelia is proposed, with A. acutiplicata as the type species, for leptocoeliid brachiopods with a small, knoblike cardinal process, a brachial valve of moderate convexity, a broad sulcus, strong plications, subparallel dorsal adductor scars, and cordate pedicle diductor scars. Atlanticocoelia occurs in benthic assemblage 4 to 5 communities of the Emsian through Eifelian Appohimchi Province of the Eastern Americas Realm.

Phylogenetic taxonomy, that component of phylogenetic systematics concerned with the verbal representation (rather than the reconstruction or estimation) of phylogenetic relationships, was developed by de Queiroz and Gauthier (1990, 1992, 1994). Under phylogenetic taxonomy, all taxon names are names of clades (i.e., an ancestor and all of that ancestor's descendants). De Queiroz and Gauthier (1990, 1992, 1994) described three possible ways of denning clade names within the phylogenetic taxonomic system: 1) node-based definitions (Figure 1.1), of the form “the most recent common ancestor of Taxon A and Taxon B, and all of that ancestor's descendants”; 2) stem-based definitions (Figure 1.2), of the form “Taxon A and all taxa sharing a more recent common ancestor with Taxon A than with Taxon B”; and 3) apomorphy-based definitions (Figure 1.3), of the form “the first taxon with derived character X and all of that ancestor's descendants.” Bryant (1994) noted that, while the first two definition types will always be stable, apomorphy-based definitions are potentially confusing if that derived character is found to occur in more than one lineage (i.e., is homoplastic). Under the phylogenetic system of taxonomy, definitions of taxon names are independent with respect to previous diagnosis (as particular character states may be found to occur in other lineages or in more inclusive clades) and composition (as particular member taxa may subsequently be found to lie outside the defined clade boundary). This paper is the initial work in an ongoing study by Holtz and Padian (1995, in preparation) to clarify the phylogenetic taxonomy of major clades of theropods and related taxa.

Diverse silicified trilobite faunas from the lower Wenlock to lower Ludlow of the Cape Phillips Formation, central Canadian Arctic, have been the subject of works by Perry and Chatterton (1977), Chatterton and Perry (1979), Adrain (1994), and Adrain and Edgecombe (1995, and in press). The present work describes a very minor component of these faunas, the family Phacopidae, which is nevertheless of considerable biogeographic interest.