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The late Paleozoic temnospondyl Sclerocephalus formed an aquatic top predator in various central European lakes of the late Carboniferous and early Permian. Despite hundreds of specimens spanning a wide range of sizes, knowledge of the endocranium (braincase and palatoquadrate) remained very insufficient in Sclerocephalus and other stereospondylomorphs because even large skulls had unossified endocrania. A new specimen from a stratigraphically ancient deposit at St. Wendel in southwestern Germany is recognized as representing a new taxon, S. concordiae new species, and reveals a completely ossified endocranium. The sphenethmoid was completely ossified from the basisphenoid to the anterior ethmoid region, co-ossified with the parasphenoid, and the basipterygoid joint was fully established. The pterygoid bears a slender, S-shaped epipterygoid, which formed a robust pillar lateral to the braincase. The massive stapes was firmly sutured to the parasphenoid. In the temnospondyl endocranium, character evolution involved various changes in the epipterygoid region, which evolved distinct morphologies in each of the major clades.UUID: http://zoobank.org/5e6d2078-eacf-4467-84cf-a12efcae7c0b

Middle meningeal vessels, dural venous sinuses, and emissary veins leave imprints and canals in the endocranium, and thus provide evidence of vascular patterns in osteological samples. This paper investigates whether craniovascular morphology undergoes changes in craniosynostotic human skulls, and if specific alterations may reflect structural and functional relationships in the cranium. The analyzed osteological sample consists of adult individuals with craniosynostoses generally associated with dolichocephalic or brachycephalic proportions, and a control sample of anatomically normal adult skulls. The pattern and dominance of the middle meningeal artery, the morphology of the confluence of the sinuses, and the size and number of the emissary foramina were evaluated. Craniovascular morphology was more diverse in craniosynostotic skulls than in anatomically normal skulls. The craniosynostotic skulls often displayed enlarged occipito-marginal sinuses and more numerous emissary foramina. The craniosynostotic skulls associated with more brachycephalic morphology often presented enlarged emissary foramina, while the craniosynostotic skulls associated with dolichocephalic effects frequently displayed more developed posterior branches of the middle meningeal artery. The course and morphology of the middle meningeal vessels, dural venous sinuses, and emissary veins in craniosynostotic skulls can be related to the redistribution of growth forces, higher intracranial pressure, venous hypertension, or thermal constraints. These functional and structural changes are of interest in both anthropology and medicine, involving epigenetic traits that concern the functional and ontogenetic balance between soft and hard tissues.

A detailed anatomy of the braincase and stapes of the subadult specimen of Diadectes absitus from early Permian sediments of Germany are described for the first time based on the high-resolution X-ray microcomputed tomography. In contrast to previous studies of Diadectes, the bones of the braincase (opisthotic, prootic, supraoccipital, basioccipital, exoccipital, basisphenoid, and sphenethmoid), and parasphenoid of D. absitus are not co-ossified, but suturally defined. This has allowed for a reconstruction of a complete braincase with all sutures between the individual bones. The opisthotic, prootic, and supraocciptal contain a well-preserved endosseous labyrinth. The three-dimensional-reconstruction of its cavities shows a well-preserved vestibule, three semicircular canals, and well-developed cochlear recess. In addition, a shallow subarcuate fossa is present on the ventral surface of the supraoccipital, which lies medial to the anterior semicircular canal. A typical feature of the diadectid braincase is the presence of the otic tube leading from the fenestra vestibuli to the vestibule. A revision of the topology of this structure is presented here. Here, we describe new structures of the stapes, especially in its proximal portion, as well as its position to the fenestra vestibuli. These structures are described for the first time not only in D. absitus, but for the genus.

Birds and crocodiles show radically different patterns of brain development, and it is of interest to compare these to determine the pattern of brain growth expected in dinosaurs. Here we provide atlases of 3D brain (endocast) reconstructions for Alligator mississippiensis (alligator) and Struthio camelus (ostrich) through ontogeny, prepared as digital restorations from CT scans of stained head and dry skull specimens. Our morphometric analysis confirms that ostrich brains do not change significantly in shape during postnatal growth, whereas alligator brains unfold from a cramped bird-like shape in the hatchling to an elongate, straight structure in the adult. We confirm that birds exhibit paedomorphic dinosaur endocranial traits such as retaining an enlarged and compact brain shape in the adult, whereas crocodiles show peramorphic traits where the brain elongates with growth as the skull elongates. These atlases of ontogenetic stages of modern bird and crocodilian endocrania provide a basis for comparison of non-avian dinosaur endocasts and consideration of the divergence of the "avian" and "crocodilian" modes of brain development and heterochronic change on phylogenies.

Narwhals (Monodon monoceros) and belugas (Delphinapterus leucas) are the only extant members of the Monodontidae, and are charismatic Arctic‐endemic cetaceans that are at risk from global change. Investigating the anatomy and sensory apparatuses of these animals is essential to understanding their ecology and evolution, and informs efforts for their conservation. Here, we use X‐ray CT scans to compare aspects of the endocranial and inner ear labyrinth anatomy of extant monodontids and use the overall morphology to draw larger inferences about the relationship between morphology and ecology. We show that differences in the shape of the brain, vasculature, and neural canals of both species may relate to differences in diving and other behaviors. The cochleae are similar in morphology in the two species, signifying similar hearing ranges and a close evolutionary relationship. Lastly, we compare two different methods for calculating 90var – a calculation independent of body size that is increasingly being used as a proxy for habitat preference. We show that a ‘direct’ angular measurement method shows significant differences between Arctic and other habitat preferences, but angle measurements based on planes through the semicircular canals do not, emphasizing the need for more detailed study and standardization of this measurement. This work represents the first comparative internal anatomical study of the endocranium and inner ear labyrinths of this small clade of toothed whales.

The purpose of this study was to examine the pattern of postnatal brain growth in two wild canid species: the coyote (Canis latrans) and gray wolf (Canis lupus). Adult regional and total brain volume differences were also compared between the two species as well as within each species by sex. Three-dimensional virtual endocasts of endocranial airspace were created from computed tomography scans of 52 coyote skulls (28 female, 24 male; 1 day to 13.4 years) and 46 gray wolf skulls (25 female, 21 male; 1 day to 7.9 years). Age was known in coyotes or estimated from dentition patterns in wolves. The 95% asymptotic growth of the endocranium is completed by 21 weeks in male and 17.5 weeks in female coyotes and by 27 weeks in male and 18.5 weeks in female wolves. These ages are well before age at first reproduction (coyote – 40.4 weeks; wolf – 91.25 weeks). Skull growth as measured by centroid size lags behind endocranial growth but is also completed before sexual maturity. Intra- and interspecific comparisons of brain volumes in the adult wolves and coyotes revealed that relative anterior cerebrum (AC) volume was greater in males than females in both species. Relative brain size was greater in the coyote than in the wolf as was relative cerebrum volume. However, relative AC volume and relative cerebellum and brainstem volume was greater in the wolf than coyote. One explanation for the increased AC volume in males compared to females may be related to the role of social information processing. However, additional data are needed to determine the correspondence between regional volumes and functional differences either between or within these species. Nonetheless, these findings provide important baseline data for further studies on wild canid brain variations and development.

International audience; BackgroundPositional skull deformities (PSD) are becoming a daily health concern for craniofacial surgeons. Several reports have indicated that cerebrospinal fluid (CSF) space increases on computed tomography (CT) scans of infants suffering from PSD, suggesting a potential causal link. Here, we describe a semi-automatic method to estimate total brain and CSF volumes quantitatively. We tested the potential correlation between total CSF volume and the occurrence of PSD.MethodsA single-center retrospective study was carried out using 79 CT scans of PSD and 60 CT scans of control subjects. The endocranium was segmented automatically using a three-dimensional deformable surface model, and the brain was segmented using a semi-automatic threshold-based method. Total CSF volume was estimated based on the difference between endocranial and brain volumes.ResultsAutomatic segmentation of the endocranium was possible in 75 CT scans. Semi-automatic brain and CSF volume evaluations were performed in 40 CT scans of infants with PSD (18 = occipital plagiocephaly, 11 = fronto-occipital plagiocephaly, and 11 = posterior brachycephaly) and in six control CT scans. Endocranial and total CSF volumes were not significantly different between patients with PSD and controls. The occipital plagiocephaly group had an enlarged brain volume compared with that in patients in the other groups.ConclusionsTotal CSF volume did not change in infants with PSD, and the results do not support a role for volume changes in CSF in the etiology of PSD. Macrocephaly in patients with occipital plagiocephaly may be a specific etiological factor compared with that in other PSDs.Keywords

The composition of the basicranial axis has been reported in the comparative literature in numerous extant and extinct mammals. The primary components are unpaired endochondral bones: the ethmoid, presphenoid, basisphenoid, and basioccipital. Ventral to these are several dermal elements: included are the unpaired vomer, which is widely present, and three bones with more limited distributions, the paired palatines, the paired pterygoids, and the unpaired parasphenoid. Here, we describe novel dermal structures on the dorsal aspect of the basicranial axis in the rock hyrax, Procavia capensis. This taxon has a medial process of the paired frontal bones that meets on the midline and overlies the presphenoid at its juncture with the ethmoid; we term this the presphenoid process of the frontal. Ventral to the presphenoid process is a second smaller process that is off the midline and presents a facet contacting a boss on the presphenoid; we term this the presphenoid facet of the frontal. Occupying the notch between these two structures is the ethmoidal nerve. We sampled the taxonomically diverse collections of the Section of Mammals, Carnegie Museum of Natural History, and the literature. We found additional instances of interfrontal contact dorsal to the ethmoid and presphenoid in the artiodactyl Neotragus and in various platyrrhine and catarrhine primates resembling the presphenoid process of the frontal of P. capensis. However, we did not find a presphenoid facet of the frontal in Neotragus and the primates, which, therefore, thus far is unique to P. capensis. Additionally, we report the presence of a midline suture on the ventral surface of the presphenoid of neonatal P. capensis, which, to our knowledge, is also unique to this mammal.

Pseudopus apodus (Pallas, 1775) is the largest extant legless species of the subfamily Anguinae (Anguimorpha, Anguidae) living mostly in the sub-arid territories ranging from the Balkan area in Europe to Kazakhstan in Asia. The species of other two genera live in North America, South-East Asia and North Africa (Ophisaurus) and Europe and South-West Asia (Anguis). The interrelationships of Anguinae are unresolved; this is in part the consequence of the insufficient knowledge of the cranial, postcranial and integumentary anatomy of the individual anguine species. The aim of this article is to fulfill this gap in our knowledge of the anguine anatomy. Now, in the first part of the project, the individual bones of the exocranium and visceral endocranium of the anguine legless lizard P. apodus are described in detail. In the present study, P. apodus is revealed to have autoapomorphic features of the skull which clearly distinguish it from Anguis and Ophisaurus. In addition, the study of posthatchling ontogeny of exocranium of P. apodus revealed some features, such as a nasal process of premaxilla being slightly widened in about its mid-length, that are also typical for adults of the Ophisaurus and Anguis species as well as extinct species of Pseudopus. This strongly indicates that peramorphic heterochronic process played role in the evolution of the P. apodus skull. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:460-502, 2017. © 2016 Wiley Periodicals, Inc.

A medical tomodensitometric study (TDM) was performed on a dry skull from the necropolis of Ancón in Peru. The skull, housed at the Muséum national d'histoire naturelle in Paris, displays an anteroposterior, brachycephalic, oblique, asymmetric, and bilobar deformation. TDM permitted 3-D reconstructions of the skull, endocranium, and vault thickness. The external surface displayed deformation and asymmetry in the bone structures and the endocranium demonstrated deformation and asymmetry in the brain lobes and superficial structures. The TDM demonstration of abnormal variations and pronounced asymmetry in the thickness of the vault strongly suggested that the deformation was ante mortem. The 3-D TDM reconstructions also helped to reconstruct the device used to deform the head.

The masticatory apparatus amongst closely related carnivoran species raises intriguing questions about the interplay between allometry, function, and phylogeny in defining interspecific variations of cranial morphology. Here we describe the gross structure of the jaw adductor muscles of several species of canid, and then examine how the muscles are scaled across the range of body sizes, phylogenies, and trophic groups. We also consider how the muscles are accommodated on the skull, and how this is influenced by differences of endocranial size. Data were collected for a suite of morphological metrics, including body mass, endocranial volume, and muscle masses and we used geometric morphometric shape analysis to reveal associated form changes. We find that all jaw adductor muscles scale isometrically against body mass, regardless of phylogeny or trophic group, but that endocranial volume scales with negative allometry against body mass. These findings suggest that head shape is partly influenced by the need to house isometrically scaling muscles on a neurocranium scaling with negative allometry. Principal component analysis suggests that skull shape changes, such as the relatively wide zygomatic arches and large sagittal crests seen in species with higher body masses, allow the skull to accommodate a relative enlargement of the jaw adductors compared with the endocranium. Anat Rec, 299:951-966, 2016. © 2016 The Authors The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc.

Holoprosencephaly is a complex malformation of the brain associated with the median facial defects. Variability of the clinical picture is the characteristic of this anomaly. In most cases, the degree of severity of the facial anomaly correlates with the degree of damage to the brain. This article aims to present a rare case of child with a milder form of brain anomaly combined with a severe form of facial anomaly. The article also presents the application of a feeding stimulator to improve the child's quality of life. The anomaly was diagnosed by postnatal sonography of the brain, magnetic resonance imaging of the endocranium, and three-dimensional computed tomography of the craniofacial skeleton.

OBJECTIVES: We describe a new computer reconstruction to obtain complete anatomical information of the ecto- and endocranium from the imperfectly preserved skull of the Neanderthal Amud 1. MATERIALS AND METHODS: Data were obtained from computed tomography scans of the fossil cranium. Adhesive and plaster were then virtually removed from the original specimen, and the fragments comprising the fossil cranium were separated. These fragments were then mathematically reassembled based on the smoothness of the joints. Both sides of the cranium were reassembled separately, and then aligned based on bilateral symmetry and the distance between the mandibular fossae obtained from the associated mandible. The position of the isolated maxilla was determined based on the position of the mandible that was anatomically articulated to the mandibular fossae. To restore missing basicranial and damaged endocranial regions, the cranium of Forbes' Quarry 1 was warped onto that of La Chapelle-aux-Saints 1, and the resulting composite Neanderthal cranium was then warped onto the reconstructed Amud 1 by an iterative thin-plate spline deformation. RESULTS: Comparison of the computer reconstruction with the original indicated that the newly reconstructed Amud 1 cranium was slightly shorter and wider in the anteroposterior and mediolateral directions, respectively, suggesting that it was relatively more brachycephalic. The endocranial volume was estimated to be 1,736 cm3 , which was quite similar to the original estimated value of 1,740 cm3 . DISCUSSION: This new computer reconstruction enables not only measurement of new cranial metrics, but also inclusion of the Amud 1 specimen in three-dimensional geometric morphometric analyses that were previously difficult due to its incompleteness.

Even after 200 years of study, some details of the cranial anatomy of ichthyosaurs, one of the most successful groups of marine vertebrates in the Mesozoic, are still unclear. New information on the braincase, palate and occiput are provided from three-dimensional scans of an exceptionally preserved ichthyosaur (‘Hauffiopteryx’ typicus) skull from the Toarcian (183–174 Ma, Lower Jurassic) of Strawberry Bank, England. This ichthyosaur has unusual, hollow, tubular hyoid bars. The occipital and braincase region is fully reconstructed, creating the first digital cranial endocast of an ichthyosaur. Enlarged optic lobes and an enlarged cerebellum suggest neuroanatomical adaptations that allowed it to be a highly mobile, visual predator. The olfactory region also appears to be enlarged, suggesting that olfaction was more important for ichthyosaurs than has been assumed. Phylogenetic analysis suggests this ichthyosaur is closely related to, but distinct from, Hauffiopteryx, and positioned within Thunnosauria, a more derived position than previously recovered. These results further our knowledge of ichthyosaur cranial anatomy in three dimensions and provide a platform in which to study the anatomical adaptations that allowed ichthyosaurs to dominate the marine realm during the Mesozoic.

Intraspecific variation of endocranial structures is not widely studied in most mammals, particularly fossil mammals, which are mainly represented by a few preserved crania. However, a description of this variation is necessary to be able to study fossil mammals from an ecological and phylogenetic perspective. To facilitate further analyses on fossil equoids, digital reconstructions of the cranial endocast, petrosal bone, and bony labyrinth were created based on CT scans, taken from a wild population of 12 Equus caballus przewalskii currently being monitored. Using descriptive, biometric, and morphometric analyses, an unsuspected range of intraspecific variation for 40 endocranial characters is revealed. Intraindividual variation can be further understood through the comparison of paired organs from a single individual. These results prompt cautious consideration of these characters, as well as an index for the determination of hearing abilities or encephalization quotients. Thanks to this work, more is now known about the intraspecific variation of the external morphology of the most frequently studied structures in the endocranium of mammals and more specifically in equoids, where no such study had been undertaken until now. This will help to improve the resolution of fossil endocranial studies.

Pauropetalichthys magnoculus , a new genus and species within the Petalichthyida (Gnathostomata: Placodermi), is described from the Late Emsian (Early Devonian) of Qujing, Yunnan, southwestern China. A three-dimensional reconstruction of the skull roof and neurocranium based on high-resolution computed tomography reveals the pattern of sensory canals, the visceral surface of the skull roof, and the profile of the endocranium. The perichondral lining of the nasal capsules provides the first hard evidence of nasal capsules in petalichthyids. A phylogenetic analysis resolves the new taxon as the most basal member of the Quasipetalichthyidae, an endemic group sister to the Macropetalichthyidae. In light of the newly revealed endocranial features, we discuss the morphological disparity of petalichthyid endocrania. The paleogeographic distribution of the Petalichthyida is summarized to show the group's center of origin and routes of dispersal.

By comparing species-specific developmental patterns, we can approach the question of how development shapes adult morphology and contributes to the evolution of novel forms. Studies of evolutionary changes to brain development in primates can provide important clues about the emergence of human cognition, but are hindered by the lack of preserved neural tissue in the fossil record. As a proxy, we study the shape of endocasts, virtual imprints of the endocranial cavity, using 3D geometric morphometrics. We have previously demonstrated that the pattern of endocranial shape development is shared by modern humans, chimpanzees and Neanderthals after the first year of life until adulthood. However, whether this represents a common hominoid mode of development is unknown. Here, we present the first characterization and comparison of ontogenetic endocranial shape changes in a cross-sectional sample of modern humans, chimpanzees, gorillas, orangutans and gibbons. Using developmental simulations, we demonstrate that from late infancy to adulthood ontogenetic trajectories are similar among all hominoid species, but differ in the amount of shape change. Furthermore, we show that during early ontogeny gorillas undergo more pronounced shape changes along this shared trajectory than do chimpanzees, indicative of a dissociation of size and shape change. As shape differences between species are apparent in even our youngest samples, our results indicate that the ontogenetic trajectories of extant hominoids diverged at an earlier stage of ontogeny but subsequently converge following the eruption of the deciduous dentition.

Micro computed tomography has revealed as yet undescribed internal braincase anatomy of the tetrapodomorph fishGogonasus andrewsaefrom the Frasnian Gogo Formation, Paddy's Valley, Kimberley Region, Western Australia. The complete material, including the cranial cavities and channels for blood vessels and nerves, reveals several notable features inside the endocranium. The ethmosphenoid unit includes a median capsule, which lies underneath the median postrostral and rostral series. Based on innervation and association with cutaneous vessels, potential electroreceptive function is inferred for this capsule. Several regions of poor ossification, including foramina for the glossopharyngeal and abducens nerves, as well as the apparent suture separating the ethmoid from the sphenoid portions of the braincase, are possibly indicative of early ontogenetic features. Former interpretations of the course for the superficial ophthalmic nerve inside the nasal capsule ofOsteolepisandGyroptychiusmay be incorrect, with new research supporting a path through the nasal septum, as inGogonasus.

The external and endocranial surfaces of the skull of the African palm civet, Nandinia binotata (Gray, 1830), are described and illustrated in detail based on 30 specimens (from Carnegie Museum of Natural History and American Museum of Natural History). With the inclusion of a newborn and six juveniles with deciduous dentitions, a reasonable ontogenetic series is represented. The bone-by-bone descriptions are primarily based on the condition in an adult female and the newborn with consideration of variation across the sample. The principal cranial foramina are treated in a glossary, and the hyoid apparatus and larynx are described from a single specimen. The sample exhibits a remarkable degree of variability in cranial features that are often used as different states of characters in phylogenetic analysis (e.g., number and position of palatal foramina, the orbital mosaic, and composition of the lacrimal foramen). Nandinia binotata, the only taxon in the Nandiniidae, has been identified as the mos...

Understanding ontogenetic and developmental patterns is critical for reconstructing the life history of fossil vertebrates. In dinosaurs, ontogenetic studies have nearly exclusively focused on changes in the cranial and post-cranial skeleton, whereas ontogenetic changes in the endocranium have received little attention. Here, we present digital reconstructions of the brain and inner ear anatomy of two ontogenetic stages of the Jurassic ornithischian dinosaur Dysalotosaurus lettowvorbecki. Results show that the endocranial anatomy underwent considerable changes during growth, including a rostrocaudal elongation of the olfactory apparatus, a reduction in the cephalic and pontine flexure and an increase in cerebellum size. Functional elements, such as the cerebral hemispheres and the inner ear, were already well developed in early ontogenetic stages, indicating a large degree of precociality. The anisotropic pattern of size and shape changes in the endocranium further indicates that ontogenetic trajectories may be controlled by functional and environmental demands in the different growth stages in Dysalotosaurus lettowvorbecki. The occurrence of similar ontogenetic patterns in the endocranial anatomy of derived ornithopod dinosaurs suggests a more widespread distribution of this growth trajectory.

The purpose of this study is to provide a detailed description of the neuroanatomy of Bonatitan, Antarctosaurus, and an unnamed titanosaur from Rio Negro, Argentina including the first observations on the inner ear of the two first taxa using CT scans. The materials were compared with previously described sauropod endocasts and other less complete titanosaur braincases from Argentina. The cranial endocasts show the general morphology of other sauropods being bulbous, anteroposteriorly short and transversely wide, and with enlarged and posteroventrally pro- jected pituitary body. Particular titanosaur traits are the extremely short and horizontal olfactory tract, the absence of a floccular process and a single root for cranial nerve XII. In addition, in the basicranium the abducens nerve (CN VI) does not penetrates the pituitary fossa and the internal carotid artery enters the medial aspect of the basipterygoid pro- cess, resulting in an external opening for this vessel that is not visible in lateral view of the braincase. The titanosaurid inner ear also exhibits par- ticular traits, such as robust semicircular canals, and anterior and poste- rior semicircular canals that are subequal in size. The variation observed in the sauropod endocranium indicates an evolutionary tendency in tita- nosaurs toward the anteroposterior shortening of the midbrain, and the reduction in size of the semicircular canals of the inner ear, in particular the anterior semicircular canal. This, together with the lack of floccular process suggests a narrower range of movements of the head for this clade. Anat Rec, 295:2141-2156, 2012. V C 2012 Wiley Periodicals, Inc.

A full description of a complete and articulated, three-dimensionally preserved, placoderm fish, Materpiscis attenboroughi (Ptyctodontida), from the Late Devonian Gogo Formation is presented. The jaw articulation is unique in being preserved in situ, providing new morphological information on the articulation of the quadrate, metapterygoid, and labial skeleton. In addition, separate hyoid and opercular cartilages are identified, thus confirming their presence for the first time within placoderms. Preserved orbital ossifications indicate an anteriomesial orientation of this braincase region. The complete scapulocoracoid provides additional morphological information on the pectoral fin articulation. A new specimen of Austroptyctodus gardineri preserving the anterior portion of the head and jaws allows for revised descriptions of the endocranium and visceral skeleton, including the most complete endocranial ossifications recovered to date. As well, elements of the labial skeleton not known previousl...

Tumors of the posterior orbit require different therapeutic modalities, depending on the histological entity. In the orbit all structures are in close relationship and the endocranium is in the direct proximity. This requires profound knowledge of topographic anatomy and high therapeutic precision. The surgical approach to the posterior orbit via a ventral intraorbital approach is strongly restricted due to the ocular bulb which consumes most space in the anterior orbit. Therefore if the bulb and vision are to be retained extraorbital surgical corridors are predominantly preferred. These are classified into extracranial and intracranial approaches. In detail, the former are medial transethmoidal orbitotomy, caudal transmaxillar orbitotomy and lateral orbitotomy. Frontolateral and frontotemporal orbitotomy as well as frontal, bifrontal and subfrontal orbitotomy are intracranial approaches. Apart from surgical methods there are several forms of radiotherapy which can be applied to orbital tumors under certain indications. Radiotherapy may be performed with external fractionated photon radiation or as stereotactic radiation, with heavy ions or protons or as brachytherapy. In this article various therapeutic interventions to the posterior orbit and the indications and potential side-effects are described.

Our recent X-ray micro computer-tomographic (μCT) investigations of Prophaethon shrubsolei and Odontopteryx toliapica from the Lower Eocene London Clay Formation of England revealed the avian brain to have been essentially modern in form by 55 Ma, but that an important vision-related synapomorphy of living birds, the eminentia sagittalis of the telencephalon, was poorly developed. This evidence suggested that the feature probably appeared close to the end of the Mesozoic. Here we use μCT analysis to describe the endocranium of Halcyornis toliapicus, also from the London Clay Formation. The affinities of Halcyornis have been hotly debated, with the taxon referred to the Charadriiformes (Laridae), Coraciiformes (Alcedinidae, and its own family Halcyornithidae) and most recently that Halcyornithidae may be a possible senior synonym of Pseudasturidae (Pan-Psittaciformes). Unlike Prophaethon and Odontopteryx, the eminentia sagittalis of Halcyornis is strongly developed and comparable to that of living species....

The social brain hypothesis posits that the demands of living in complex social groups require increased neural processing, and that this underlies the expansion of brain areas involved in mediation of complex social behavior. However, much of the support for the social brain hypothesis is derived from comparative studies in primates. If large brains evolved as a result of selection pressures imposed by life within complex societies, as the social brain hypothesis predicts, then gregarious nonprimate species should possess large brains and exhibit comparable expansion of brain areas mediating social behavior. Our purpose here was to test a prediction of the social brain hypothesis – that increased brain size is related to social complexity – by examining species in the carnivore family Hyaenidae. Hyaenidae contains 4 extant species that span a spectrum of social complexity: the aardwolf (Proteles cristata) is solitary during the nonbreeding season, and forms monogamous pairs during the breeding season; the striped hyena (Hyaena hyaena) lives solitarily or in small groups; the brown hyena (Parahyaena brunnea) lives in groups of up to 14 individuals; and the spotted hyena (Crocuta crocuta) lives in complex hierarchically organized groups containing up to 90 animals. Computed tomography was used to create three-dimensional endocasts based on serial analysis of coronal sections of the adult endocranium. The largest brain volume, relative to body size, is found in the spotted hyena. We found no significant variation in relative brain volume among striped hyenas, brown hyenas, and aardwolves. The spotted hyena also possesses a larger anterior cerebrum volume relative to total brain volume than is found in the other hyena species; this region is composed primarily of frontal cortex. These data are consistent with the idea that expansion of the frontal cortex is driven by the demands of processing cognitive information associated with complex social lives, but other factors may drive the evolution of large brains in hyaenids.

Cranial morphological features of the stem-group sarcopterygian Guiyu oneiros Zhu et al., 2009 provided here include the dermal bone pattern and anatomical details of the ethmosphenoid. Based on those features, we restored, for the first time, the skull roof bone pattern in the Guiyu clade that comprises Psarolepis and Achoania. Comparisons with Onychodus, Achoania, coelacanths, and actinopterygians show that the posterior nostril enclosed by the preorbital or the preorbital process is shared by actinopterygians and sarcopterygians, and the lachrymals in sarcopterygians and actinopterygians are not homologous. The endocranium closely resembles that of Psarolepis, Achoania and Onychodus; however, the attachment area of the vomer possesses irregular ridges and grooves as in Youngolepis and Diabolepis. The orbito-nasal canal is positioned mesial to the nasal capsule as in Youngolepis and porolepiforms. The position of the hypophysial canal at the same level or slightly anterior to the ethmoid articulation represents a synapmorphy of the Guiyu clade. The large attachment area of the basicranial muscle indicates the presence of a well-developed intracranial joint in Guiyu.

Polazzodus coronatus, gen. et sp. nov., is a pycnodontiform fish from two proximate Late Cretaceous fossil sites near Polazzo, in northeastern Italy, where it is relatively abundant. Its autapomorphic characters are the presence of a distinctively shaped second dorsal ridge scale with an anterior projection; the presence of an olfactory fenestra on the premaxilla; an axe blade-like morphology of the maxilla; and the presence of a conspicuous posterodorsal process on the cleithrum. Polazzodus coronatus, gen. et sp. nov., is closely related to the pycnodontids Oropycnodus, Pycnodus, and probably ‘Coelodus’ gridelli and Tergestinia. Although their phylogenetic interrelationships will be tested when the last two forms are revised, Polazzodus coronatus is assigned to the subfamily Pycnodontinae within the Family Pycnodontidae, because it possesses the autapomorphies of both latter groups; for instance, the presence of an exposed part of the endocranium, without overlying dermal bones, which is an auta...

An incomplete braincase from the Upper Cretaceous Portezuelo Formation of northwestern Patagonia (Neuquen Province, Argentina) is described. The specimen preserves the lateral walls formed by the laterosphenoid, probably part of the orbitosphenoid, prootic, the exoccipital-opisthotic complex and fragments of the frontal, parietal and basisphenoid. Both inner ears are preserved allowing the production of latex endocasts. The external and internal morphology of the laterosphenoid and the prootic, the absence of a floccular recess, and the morphology and position of the cranial nerves V–VII, the oval window and the metotic foramen indicate that the new braincase belongs to a sauropod dinosaur, probably a titanosaur. The morphology of the inner ear is also reminiscent of that of Sauropoda, which is characterized by the presence of a simple, short and conical lagena, a posterior semicircular canal that is larger than the lateral semicircular canal, an anterior semicircular canal that is larger than the other two, and an angle between the vertical semicircular canals (anterior and posterior) of approximately 90°.

New data are presented on the neurocranial complex (endocranium plus intimately associated bones of the palate) of the Late Devonian (Famennian) 'rhynchodipterid' lungfish Soederberghia groenlandica from the Aina Dal Formation (Celsius Bjerg Group) of East Greenland. Only the otic and occipital regions of the braincase are ossified in Soederberghia. The neurocranium of this genus shares a series of derived features with 'Griphognathus' whitei, including a cranial centrum, fenestrate lateral cristae, and gutters on the ventral surface of the parasphenoid interpreted as accommodating the lateral dorsal aortae. The interrelationships of early lungfishes have been the subject of considerable disagreement. New data from Soederberghia are coupled with a data set focused on the character-rich neurocranial complex in order to examine the systematic utility of this underexploited morphological system. Different methods of phylogenetic inference (maximum parsimony, Bayesian) return broadly consistent results. The Early to Middle Devonian forms Dipnorhynchus, Stomiahykus and Uranolophus are placed among the most basal of lungfishes. 'Holodontids' plus 'rhynchodipterids' (comprising Griphognathus and Soederberghia) occupy an apical position, and are separated from the earliest lungfishes by a paraphyletic assemblage of taxa generally identified as 'chirodipterids' and 'dipterids.' This finds broad agreement with the results of previous cladistic studies focused on non-neurocranial data sets, but diverges from functional-adaptive scenarios that posit three lineages of early lungfishes based on aspects of the dentition. As currently defined, both 'chirodipterids' and the genus Chirodipterus are heterogeneous assemblages; this analysis fails to find support for the monophyly of either. While this study indicates that Griphognathus is probably paraphyletic, it nevertheless supports a close relationship between the nominal species of this genus and Soederberghia.© 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 115-171. © 2007 The Linnean Society of London.

The development of computer tomography and image processing has made it possible to establish virtual 3D reconstruction and non-invasive dissection of fossil specimens. We used these methods to reconstruct a virtual 3D skull of a Pleistocene cheetah skull from the Tuozi cave, Tangshan, Nanjing, and virtually dissected it for anatomic studies, and measured the volumes of different parts of the endocranium. The endocranium of the cheetah skull has showed that its frontal sinus is beehive-tike, the frontal lobe of cerebra is relatively large but the temporal lobe is relatively small, its cerebral sulcus and gyrus are more complicated than those of the domestic cat, similar to those of the domestic dog, but simpler than those of giant panda, pig, cattle and horse. The technology of virtual 3D reconstruction and non-invasive dissection of fossil specimens can extend the morphological study from the exterior to the interior, and it can also help to study fragile specimens and virtually backup rare and precious specimens.

A well-preserved neurocranium with attached partial skull roof is described from the Early Devonian Taemas Formation at Wee Jasper, southern New South Wales, Australia. The dermal ornament, skull roof pattern, and general proportion and structure of the endocranium are typically actinopterygian and the specimen is tentatively assigned to the actinopterygian genus Ligulalepsis. Other features more closely resemble some other groups, such as sarcopterygians (widely-spaced orbital walls, and short, broad telencephalon cavity), acanthodians (position of hyo-mandibular facet), and placoderms (many similarities including position of foramina for oculomotor, profundus, and trigeminal nerves, pituitary vein, and ophthalmic and orbital arteries in and around the orbit). This specimen is the first early osteichthyan to demonstrate the presence of an eyestalk, previously known only in placoderms and chondrichthyans. The unusual mix of characters and presence of an eyestalk provide new insights into primitiv...