In neoceratopsian dinosaurs, the centra, neural arches, and neural spines of several anteriormost cervical vertebrae are fused together to form a structure called the cervical bar (Langston, 1975) or syncervical (Ostrom and Wellnhofer, 1986). This structure characterizes all neoceratopsians (Dodson and Currie, 1990; Dodson et al., 2004; You and Dodson, 2004) for which the anterior cervicals are known, but it remains controversial how many vertebrae are fused together to produce this structure, namely, whether it consists of the first three (atlas through the third cervical) or four (atlas through the fourth cervical) elements. Analyses of ceratopsian interrelationships have employed from two (Sereno, 1984; Chinnery, 2004) to five (Xu et al., 2002) characters related to the cervical bar; accordingly, sorting out the exact identities of the elements contributing to this structure may have implications for our understanding of support, branch lengths, and rates in ceratopsian evolution.

Pharciceras Hyatt, 1884 is the diagnostic ammonoid of the late middle Givetian Stage of the Middle Devonian Series. It occurs in the Rhenish Massif in Germany, the Montagne Noire in southern France, and in equivalent strata in the Anti-Atlas in southern Morocco. Verified North American occurrences of Pharciceras are confined to the New York succession, where the appearance of the ancestral species P. amplexum (Hall, 1886) in the Upper Tully Limestone represents an important and well-established biostratigraphic datum within the Taghanic onlap interval (see Aboussalam and Becker, 2001 for discussion). In this note we describe a second, distinctly younger, North American species, Pharciceras barnetti n. sp., from the New Albany Shale in eastcentral Kentucky that provides new evidence on the Taghanic onlap interval (Upper Tully/Geneseo Sequence of Baird and Brett, 2003) in the central Appalachian Basin. This occurrence is particularly significant because of its association with conodonts that provide a basis for refined correlations between the central Appalachian Basin and the Taghanic onlap succession in New York.

Macropyge (Promacropyge) scandinavica new species is described from the Furongian Peltura minor Zone on northwestern Mount Kinnekulle, southcentral Sweden. It represents the first macropyginid trilobite recorded in Baltica. M. (P.) scandinavica closely resembles other species of the same subgenus from southeast China, suggesting a correlation between the Scandinavian P. minor Zone and the Lotagnostus americanus-Hedinaspis regalis Zone of China. The specimens are preserved in two limestone lithologies, interpreted as representing alternating normal and storm deposits, supporting the idea of an intrabasinal paleohigh in Västergötland, southcentral Sweden.

Boulders of late Cambrian age in conglomerates in Quebec and Newfoundland have been intensively collected and have yielded some 18 species which were referred by Ludvigsen et al. (1989) to either Theodenisia Clark, 1948, or to Peracheilus Ludvigsen, 1986. Most specimens are cranidia, rarely having the free cheek in place, and all 3 mm or less in length (sag.). Similar cranidia from strata in Vermont (Clark and Shaw, 1968), Maryland (Rasetti, 1959), Oklahoma (Stitt, 1971), Texas (Winston and Nicholls, 1967) and Alberta (Westrop, 1986) appear to be few and are in need of further study. No even partially complete exoskeleton has been found, so that isolated pygidia cannot confidently be referred to a particular species; no hypostome is known. The cranidium provides a limited basis on which to diagnose a genus, and while each of the species displays distinctive characters, it is difficult to discern one or more related groups among them. The present investigation of the holotypes of type species and material of four additional species shows how problematic is the use of current generic categories. I begin my account by pointing out differences in appearance between individual specimens. Such contrasts are greatest between the external surface of the exoskeleton and a mold of the inner, visceral surface, lesser differences resulting from exfoliation of the laminated outer layer of the exoskeleton (Fig. 1) at different levels. The holotype cranidium of Theodenisia, T. eminens (Clark, 1924) is a unique specimen, none other like it having been recovered, despite the intensive collecting. It has distinctive features, but because of its uniqueness I advocate that the name Theodenisia should only be used for this holotype (Fig. 2.1–2.3, 2.5, 2.6). The holotype and additional specimens of Peracheilus marcoui (Raymond, 1924), the type species of the genus Peracheilus, are described (Fig. 2.4, 2.7–2.15), together with four other species. These show (Figs. 3, 4) part of the range of morphology that exists, but there is little in common between them. For example, not all have S1 and S2 prominent, nor is the glabella widest anteriorly in all. Renewed intensive collecting, including from areas other than Quebec and Newfoundland, is needed in the hope of obtaining more nearly complete knowledge of the exoskeleton. Such knowledge may show whether or not a group, or groups, of related species can be recognized. As a temporary expedient I use Peracheilus? as a genus in which to include, with question, three of the species, and adopt the more recently proposed name Calculites Fortey, 1983 for the type species Acheilus microps Rasetti, 1944. In recording the material examined, I include isolated pygidia associated with cranidia in Rasetti's collection to show that they are present, but not to confirm that I consider they belong to the same species as the cranidium.

Ossified clavicles, either as paired elements or as a median furcula, have been recorded in all major clades of dinosaurs, including ornithischians, sauropodomorphs, and theropods (Bryant and Russell, 1993). Nearly all but the most basal theropods, Eoraptor lunensis and Herrerasaurus ischigualastensis, have an ossified furcula including coelophysids (Downs, 2000; Tykoski et al., 2002; Carrano et al., 2005), allosauroids (Chure and Madsen, 1996), tyrannosaurids (Makovicky and Currie, 1998; Larson and Donnan, 2002; Brochu, 2003; Lipkin and Sereno, 2004; Larson and Rigby, 2005), therizinosaurids (Xu et al., 1999a; Zhang et al., 2001), oviraptorids (Barsbold, 1983; Clark et al., 1999, 2001; Hwang et al., 2002; Osmólska et al., 2004), troodontids (Xu and Norell, 2004), and dromaeosaurids (Norell et al., 1997; Norell and Makovicky, 1999; Xu et al., 1999b; Burnham et al., 2000; Hwang et al., 2002). No ossification of any element beyond the coracoid has been found in the pectoral girdle of the well-preserved primitive theropods, Eoraptor lunensis and Herrerasaurus ischigualastensis.

De Wever et al. (1979) proposed the new radiolarian name Xiphotheca from the Triassic of Greece. We discovered that this name has already been used for a fish by Agassiz in 1846. Therefore, in accordance with article 60 of the International Code of Zoological Nomenclature (1999) we propose the name Xiphothecaella nomen novum as a replacement name (type species Xiphotheca karpenissionensis De Wever, in De Wever et al., 1979, p. 93, pl. 7, figs. 1–5; text-fig. 3, by original designation) for the preoccupied homonym Xiphotheca De Wever, 1979, non Agassiz 1846.

We describe the integumentary anatomy of titanosaur sauropod embryos from the Auca Mahuevo nesting site. Natural (calcitic) casts of the skin show the non-imbricating, tuberculate scales (i.e., tubercles) typical of other non-avian dinosaurs. However, a variety of scale patterns previously unknown for the skin of these animals is reported. The observed integumentary patterns include ground tubercles, large and elongated tubercles, parallel rows of large tubercles, tubercles in rosette-like and flower-like arrangements, and in striate-like rows. Ground tubercles and rosette-like patterns resemble the few examples of skin known for adult sauropods. The former pattern also resembles the arrangement of osteoderms of the armored titanosaur Saltasaurus. Although the embryonic skin does not show definitive evidence of armor, the posthatching development of osteoderms cannot be ruled out. This material, the only available evidence of the embryonic skin of non-avian dinosaurs, contributes significantly to our knowledge of the integumentary morphology of these animals.

The skull and mandible of Nothodipoides Korth are described. There are a number of adaptations present that are shared with other rodents with tooth-digging behavior (procumbent, elongated, and flattened incisors; anteriorly tilted occipital; strongly arched upper diastema). A new tribe of Castoroidinae, Nothodipoidini, is proposed for Nothodipoides and Microdipoides Korth and Stout, based on the fossorial adaptations of the skull, and their generally smaller size. It appears that fossorial adaptations have occurred in castorids at least three times: the Palaeocastorinae (Whitneyan through Arikareean), the primitive beaver Migmacastor (Arikareean), and the Nothodipoidini (late Barstovian through the Clarendonian).

Sponges, along with scleractinian corals, are among the main reef-building organisms in Triassic reefs. Hypercalcified groups, including the chambered sphinctozoans, and the unchambered inozoans, chaetetids, and spongiomorphids, represent the most abundant Triassic reef-building sponges. Earlier workers have described elements of the latter group as “hydrozoans.” Hexactinellid sponges, abundant in some Permian reefs (e.g., in Texas, Finks, 1960), are rarely known from similar Triassic deposits, in general (Tichy, 1975), and particularly from Upper Triassic stratigraphic units. Hexactinellid sponges have been sporadically reported from well-investigated Upper Triassic reefs in the western Tethyan region (e.g., Keupp et al., 1989). However, a variety of hexactinellid sponges have been reported from Upper Triassic deposits and reefal limestones of the northern and central Tethyan realm (Boiko, 1990; Wu, 1989; Wu and Xiao, 1989; Rigby et al., 1998).

O'Dogherty (1994) erected the genus Pogonias for a distinctive group of Cretaceous radiolarians characterized by a tetrahedral thoracic segment drawn out distally into divergent appendages and considered, from a stratigraphic point of view, as a useful marker for the Albian-Turonian interval. By chance, we have recently discovered that the name Pogonias has been preoccupied two times, first by a fish Pogonias La Cepède, 1801 (p. 137), and later by an aves Pogonias Illiger, 1811 (p. 202). Thus, in accordance with the requirements of the International Code of Zoological Nomenclature (1999, article 60), we proposed the name Pogonisella nomen novum as a replacement name for Pogonias O'Dogherty, 1994, not Pogonias La Cepède, 1801, not Pogonias Illiger, 1811. The type species of Pogonisella (feminine gender) is P. prodromus by original designation (O'Dogherty, 1994).