Late Tertiary Carnivores are rare as reported in the fossil record for Mexico. The felids discussed in this paper from the state of Guanajuato represent the most diverse assemblage of this taxonomic group thus far known from the country. They include Machairodus cf. M. coloradensis, Pseudaelurus? intrepidus, and Felis cf. F. studeri. The last-named taxon has not previously been recognized from the late Tertiary of Mexico, and Pseudaelurus has only questionably been identified in the country (but not described or discussed). None of these taxa have yet been reported from areas further south. While age determinations for the above felids from Guanajuato were based on associated faunal constituents, especially abundant and diverse equids, the felids themselves can be useful as chronostratigraphic indicators.

Previously described upper and lower molars from the Fort Union Formation (Swain Quarry, Wyoming) are referred to Swaindelphys cifellii new genus and species. This taxon is assigned to the subfamily Herpetotheriinae, family Didelphidae. These molars were originally referred to a new, unnamed species of Peradectes (subfamily Peradectinae), with similarities to P. pusillus (now Thylacodon pusillus) and P. elegans. However, upper molars differ from these taxa in being dilambdodont, in possessing more strongly developed stylar cusps, especially on M2 and M3, and in having a protocone that is shifted anteriorly. These characters suggest similarity to taxa such as Peratherium (subfamily Herpetotheriinae, family Didelphidae), rather than Peradectes. The assignment of the lower molars from Swain Quarry is more problematic: these molars are similar to the holotype Thylacodon pusillus in that the entoconid and hypoconulid separated by a strong notch; however, the Swain Quarry lower molars differ in being smaller overall and possessing an anteroposteriorly shorter talonid. These lower molars are similar to didelphid lower molars in having a hypoconulid that is lower than the entoconid (these are subequal in height on lower molars of Peradectes), but differ from didelphid lower molars in that the hypoconulid does not form a low, posteriorly projecting shelf. Nevertheless, the upper and lower molars from Swain Quarry are considered to belong to a single taxon, and with the assignment of the Swain Quarry materials to the subfamily Herpetotheriinae, the geological range of this subfamily is extended from the early Eocene back into the middle Paleocene (Torrejonian, or To3).

George frederic matthew studied the geology of eastern Canada during the late 1800's to early 1900's and became an authority on Cambrian paleontology. Matthew advised the Geological Survey of Canada as its Cambrian expert and published over 200 papers spanning topics from Precambrian stromatolites to Pennsylvanian arthropods to archaeology (Miller, 1988a; Landing and Miller, 1988). He described a number of trace fossils and problematica cited in Hantzschel (1975), but the location of some specimens and their status has been uncertain, sometimes considered missing. Most of the specimens have now been located and this paper summarizes their current location.

A new genus and species of thylacinid, Muribacinus gadiyuli, is described from Miocene deposits of Riversleigh in northwestern Queensland. Muribacinus gadiyuli shares six character states associated with carnassialisation common among thylacinids, but is uniformly less derived for each. The closest affinities of this species lie with another plesiomorphic thylacinid from Riversleigh, Nimbacinus dicksoni. Two previously recognised thylacinid synapomorphies are reconsidered in the light of new evidence. A growing body of molecular and fossil data indicates that the modern dasyurid radiation is a relatively recent phenomenon. Character analysis suggests that no reliable dental synapomorphies define the Dasyuridae at present. It is proposed that a number of plesiomorphic late Oligocene and Miocene taxa previously considered as dasyurids be regarded as Dasyuromorphia incertae sedis pending the identification of shared derived dental characters for the family, or the discovery of more complete material.

Unusual preservation of blastoid hydrospire meshwork in a single Mississippian specimen was described by Beaver (1981). Examination of additional specimens from different stratigraphic units has revealed other specimens of Mississippian age showing the same hydrospire meshwork.

Kellogg (1936, p. 242) described “an imperfectly preserved dorsal vertebra” from Texas, which he assigned to the primitive cetacean genus Protocetus. McLeod and Barnes (1990), however, were the first to report unequivocal protocetid remains from the Atlantic Coastal Plain. Since then, Hulbert and Petkewich (1991) and Hulbert (1993) have noted a well-preserved skeleton of a protocetid cetacean from middle Eocene deposits in Georgia. The purpose of this note is to report the recent discovery of additional protocetid remains from the coastal plain of South Carolina and to discuss their stratigraphic and biostratigraphic context.

One of the rarest pterosaurs from the Upper Jurassic Solnhofen Limestone of southern Germany is Pterodactylus suevicus. Only two specimens are known: the holotype, consisting of a virtually complete skeleton described by Quenstedt (1855); and a second specimen, consisting of only postcranial elements described by Wagner (1858) and lost during World War II (Wellnhofer, 1970). Seeley (1870) noted that P. suevicus differed from P. antiquus, the type species of Pterodactylus, in a number of significant points. Therefore, he placed P. suevicus in a new genus, Cycnorhamphus. Seeley (1870:111) gave the following diagnosis of Cycnorhamphus:

The character “nares very small” was the result of a misinterpretation of depressions on the premaxillae that probably resulted from crushing, and “middle hole of the skull” referred to the confluent naris and antorbital fenestra, which Seeley apparently considered the antorbital fenestra alone.

In a recent paper D'Alessandro and Iannone (1993) introduced the new ichnogenus Caudichnus, with one ichnospecies Caudichnus annulatus, for drum-shaped trace fossils. The trace fossil comprises several structural elements and, in order to provide a uniform terminology, these elements are denned in Figure 1.

This paper describes the petrosal (periotic) and the inner ear of Herpetocetus sp., an archaic mysticete whale (Mysticeti, Mammalia) from the Yorktown Formation (Pliocene) of North Carolina, USA. Parsimony analysis of 28 petrosal characters of Herpetocetus sp. and 11 other cetacean taxa supports the monophyly of mysticetes and the division of odontocetes and mysticetes. The in-group taxa of this analysis are: Herpetocetus, Parietobalaena, Pelocetus, Balaenidae, Eschrichtius, and Balaenopteridae. Odontocetes and the archaeocete Zygorhiza were used as successive outgroups to root phylogenetic trees and to establish character polarities. Among the modern mysticetes, the Balaenopteridae (rorquals) and the Eschrichtiidae (gray whales) are more closely related to each other than either is to the Balaenidae (bowhead and right whales). Several Miocene “cetotheriid” mysticetes and balaenids share some resemblance in the petrosal, suggesting their affinities. Quantitative information of the inner ear of Herpetocetus sp. was obtained by serial sectioning and computer graphic reconstruction. Herpetocetus sp. is much less developed than odontocetes in the cochlear structures that are crucial for high frequency hearing. Some cochlear structures in this fossil mysticete resemble more closely the non-echolocating modern mysticetes than early fossil toothed whales, indicating a possible specialization in low frequency hearing. This suggests that the archaic mysticetes of the Miocene and Pliocene did not have high frequency hearing necessary for echolocation. Herpetocetus sp. is similar to modern mysticetes but different from odontocetes in the spherical shape of the vestibule.

The first occurrence of Discoaster diastypus Bramlette and Sullivan is a marker for the CP8/CP9 zonal boundary in the widely used nannofossil zonation of Okada and Bukry (1980). This zonal boundary has commonly been used to approximate the Paleocene/Eocene boundary (e.g., Berggren et al., 1985; Perch-Nielsen, 1985). In spite of the frequent use and importance of D. diastypus in biostratigraphy, there has been some confusion about this species in the literature, including some of the most used references. For instance, Bramlette and Sullivan (1961), who first described the species, incorrectly defined D. diastypus in terms of its ray number and size (see Figure 1), and included a specimen of Discoaster falcatus Bramlette and Sullivan as an isotype of D. diastypus (Bramlette and Sullivan, 1961, pi. 11, fig. 6). Perch-Nielsen (1971, pi. 51, figs. 8 and 10) figured a specimen of Discoaster barbadiensis Tan and another specimen of Discoaster bifax Bukry as D. diastypus. These mistakes apparently have gone unnoticed and were adopted by Romein (1979, p. 168) and incorporated in the Handbook of Cenozoic Calcareous Nannoplankton (Aubry, 1984, p. 46, fig. 111; p. 48, figs. 114 and 115).

The monoplacophoran genus Protoconus Stinchcomb, 1986, from the Upper Cambrian of the Ozark Uplift of Missouri, is a junior homonym of the monoplacophoran Protoconus Yü, 1979. Protoconus is a significant element in the pre-trilobite Lowermost Cambrian (Meishucan) beds of China (Yü, 1987). In consideration of this homonymy, it is proposed that Protoconus Stinchcomb, 1986, is changed and designated as Proteroconus.

Upper Pennsylvanian dysoxic marine shales of midcontinent North America yield permineralized remains of apparently extrabasinal vegetation. A large percentage of the plants are surprisingly unlike the well known swamp, fluvial and lacustrian floras of the late Paleozoic paleotropics, revealing numerous aspects of the morphology, anatomy and reproductive biology of plants that may have been ancestral to the dominant taxa of the Mesozoic. Included among the assemblages are ovulate coniferophyte remains that demonstrate the occurrence of vojnovskyalean seed plants in equatorial Euramerica. Specimens consist of simple ovulate cones that are more-or-less clustered along eustelic stems in the axils of helically arranged, strap-shaped leaf bases, and are described as Sergeia neuburgii new genus and species. Individual cones are up to approximately 2 cm long and 1.5 cm in maximum diameter, with helically arranged scales and sporophylls that diverge from a eustelic axis. Scales occur in the basal region of the cone, and are laminar and pointed. Sporophylls are borne distally. One specimen shows about 45 sporophylls, each of which terminates as one erect ovule. Most of the other cones have abraded apices, and terminate in relatively terete foliar appendages that are interpreted to be sporophyll bases. Ovules are flattened and winged, approaching 180° rotational symmetry. Integument histology, vascular tissue distribution and pollen chamber structure are similar to those of cordaiteans and callistophytalean seed ferns. Sergeia adds to the number of late Paleozoic conifer-like plants that do not conform to the Pinopsida as traditionally circumscribed, and poses additional questions to assumptions of monophyly for coniferophytes and for conifers sensu lato.

Distinctive galls have been found on a fossil oak leaf from the Miocene Gillam Springs Flora of Washoe County, Nevada. The described galls are located on the leaf surface of Quercus hannibali Dorf, an analogue of the modern species Q. chrysolepis Liebmann. Similar galls are found on extant Quercus, but the fossils seem distinctive enough to warrant description as Antronoides schorni new genus and species. The occurrence of Antronoides schorni coincides with a rapid episode of change from a mesic to a more xeric habitat, with a concomitant shift from an oak-dominated to a conifer-dominated paleoflora. Recent work suggests that speciation and radiation of galling insects is highest in xeric environments, possibly due to decreases in rates of parasitism and disease. This pattern has been documented for modern galling insects and fits the qualitative fossil evidence we present. These galls also support the hypothesis that cynipids in the Antron group originated in Nevada or eastern California and migrated from their point of origin to their current range in the Sierra Nevada and Coast Ranges.