Paroccipital Process Research Articles

Relationship of Nandinia binotata (Gray) to the Superfamily Feloidea (Mammalia, Carnivora)

The phylogenetic relationship between Nandinia binotata and Feloidea is analysed by the cladistic method, based on a literature review of osteological characters used in systematic works on carnivores for more than a century. The reduced or lost postglenoid foramen is a synapomorphy that define Nandinia and Feloidea as a monophyletic group. Nandinia does not have an ectotympanic septum in the bulla nor a paroccipital process nested with the posterior wall of the bulla, which are autapomorphies for the Feloidea. Thus it is hypothesized that Nandinia binotata has a sister‐group relation to Feloidea. The cartilaginous caudal entotympanic is an autapomorphy for Nandinia.

The evolution of the basicranium in the Henophidia (Reptilia: Serpentes)

In lizards, a short Vidian canal pierces the base of the basipterygoid process. In snakes, the anterior opening of the primitively short Vidian canal lies on the dorsal surface of the basisphenoid, trapped in an intracranial position by downgrowths of the frontal and parietal which meet the lateral edges of the basisphenoid-parasphenoid complex. This condition is observed in anilioid snakes which retain other primitive features in the braincase: the paroccipital process and the spheno-occipital tubercle (Aniliidae only) and participation of the basioccipital in the apertura lateralis of the recessus scalae tympani. Subsequent evolution within booid snakes shows a shift of the anterior opening of the Vidian canal around the anterior edge of the basisphenoid, thus acquiring a secondary extracranial position. This occurs in parallel within boine and pythonine snakes. Dinilysia shows a parallel development of die condition observed in advanced booid snakes. Pseudoboa, with its short Vidian canal opening in-tracranially, demonstrates that caenophidians originated from a basal henophidian or pre-henophidian stock. The Acrochordidae show a basicranium that can be interpreted as either primitive henophidian or primitive caenophidian.

The Skull of the Chameleon, Lophosaura ventralis (Gray); some Developmental Stages.

Summary.Graphic reconstructions are given of ne cnondrocranium and membrane bone structures of embryos of Lophsaura ventralis (Gray), head‐lengths 4.5 and 6.5 mm.; also of the temporal region of an embryo near hatching stage, and a sketch is given of the temporal region of an adult Lophosaura.The chondrocranium of Lophosaura conforms in essentials to the general lacertilian plan, but has very obvious specializations which appear to be correlated with the large size of the orbit and with the adaptations of the feeding mechanism with its large tongue. The specializations are the telescoping of the ethmoidal region, the exceptional height of the interorbital septum and the reduction of the supraseptals, the vestigial condition of the ascending process, and the degeneration of the joint between the basitrabeeular process and the pterygoid bone.Although the basitrabecular joint is akinetic, yet tho quadrate is fully streptastylic and widely separated from the jugal.The bony casque structure at the back of the skull is formed by the parietal processes which meet in the dorsal median line and extend backwards in a prominent roof or crest. The squamosals are also elongated and the superior temporal fossa enlarged, but Lophosaura differs from Chameleo in that the squamosals are separated by the parietal crest instead of extending with the parietal rod; in Chameleo they almost meet in the median dorsal line.The casque structure seems to be correlated with the increased jaw muscle development associated with the streptostylism of the quadrate; with the rigid upper jaw and the akinetism of the akinetism joint these muscles give a rapid snapping action to the jaws which is associated with the tongue mechanism. Lophosaura has a tiny tabular (supratemporal) wedged between the squamosal, the quadrate, and the paroccipital process; it is a bone of the occiput.The problem of the temporal bones in lizards is fully discussed and the differing view‐points of Broom, de Beer and Parrington, Gaupp, and Watson (1914) are tabulated.

Observations on the Anatomy of the Shoe‐bill (Balæniceps rex) and allied Birds.

Summary of Muscular Anatomy.Garrod̂s hope, excited by his extraordinarily interesting pioneer work, that muscular anatomy would furnish a sure clue to the classification of birds has not been fulfilled. Garrod relied chiefly on the presence or absence of certain muscles which he found to vary from group to group. Gadow, who has attempted on a complete scale to apply to the system Garrod̂s group of muscles, using the additional facts made known by Beddard and other writers, appreciated that as these muscles were a common heritage of all birds, the presence of any of them in any group of birds could not be taken as a guide to the systematic position of that group. He was disposed, however, to attach value to the loss of any of these muscles, and accordingly regarded the loss of this or that muscle as one of the characters to be employed in judging of the relationships of groups. Even this cautious use seems to me to be going too far. At present I do not know of any reason why we should suppose that a particular muscle may not have been lost independently many times; that is to say of any reason why a bird that has lost its femoro‐caudal muscle should be more nearly related to another bird with a similar loss than to a bird which has retained the possession once common to all three. The loss is what I have described as a multiradial apocentricity. Possibly when we know as much of the development and morphology of the muscles used by Garrod, as Fürbringer has taught us in the case of the shoulder and wing muscles, we shall be able to make move definite use of muscular anatomy in systematic ornithology. As, however, muscular anatomy has been used freely, I may give a summary of the chief facts from which more confident anatomists would draw inferences.Summary of Osteological Notes.There is a strong general resemblance between Balæniceps, on the one hand, and Scopus, Herons and Storks on the other. Balæniceps stands alone in its general proportions, in the structure and relationship of the lacrymal, quadratojugal bar, atlas, posterior lateral process of the sternum, and the humerus.Balæniceps and Scopus agree, opposed to the others, in the impervious nostrils, the union of the inner plates of the palatines, the processes bounding the temporal cavity, the acrocoracoid articulation of the clavicle, and the shortness of the tip of the clavicle.Balæniceps, Scopus and Storks agree, opposed to the others, in the basi‐temporal plate, the complete interorbital septum, the very small vomer, the shape of the posterior notch of the sternum, the absence of a spina interna, and of a median process between the diverging arms of the furcula, and the presence of a notch separating the posterior extremities of the ischium and ilium.Balæniceps and Storks agree, opposed to the others, in the large procoracoid, and the smooth edge of the post‐acetabular ilium. Of the Storks, Tantalus shows the closest agreement with Balæniceps in the occipital condyle, the paroccipital processes and the basisphenoid.Balæniceps and Herons and Scopus agree, to the exclusion of the others, in the proportions of the pelvis, and the complex hypotarsus.I have been unable to find any osteological points in which Balæniceps agrees with Herons to the exclusion of the others.