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Thesis (Ph. D.)--Universiteit van Amsterdam, 1909. / Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 75-81).

This work describes the morphology of the teeth of Triturus vulgaris and Salamandra salamandra. Tadpoles and adult animals were examined together with specimens of Amblystoma mexicanum. Hypogeophis alternans. Rana temporaria and Protopterus aethiopicus. The descriptions of the gross morphology and development confirms those of many previous workers. In addition the unique pulp structure is described as a specialisation associated with an extradental capillary network. The teeth of tadpoles and adults are fundamentally different; tadpoles possess many simple teeth with mesodermal enamel, comparable to those of many fish, but after metamorphosis there are fewer teeth which are bicuspid and have ectodermal enamel such as is found in all tetrapods. The arrangement of the teeth in fields associated with certain dermal bones is described. Throughout larval growth the skull shape changes imposing a corresponding modification in dentition; at metamorphosis gross reorganisation occurs, coronoid and palatine bones and teeth are lost and the remainingbones retain only single rows of bicuspid teeth. The organisation of the teeth in the Urodeles is unique, and shows during ontogeny the transition between aquatic and terrestrial tetrapods which must have occurred during vertebrate evolution. Urodele teeth are similar to those of the Anura and completely disimilar to those of the Dipnoa, and thus this study does not confirm the theories of Save-Soderburg and Holmgren, but suggests that the Amphibians are a natural group unrelated to the Dipnoans but possessing features in common with all other Tetrapods.

According to von Frisch (1911) a melanophore-aggregating centre exists in the medulla of the minnow, Phoxinus phoxinus L. From the medulla spinal pigmento-motor fibres pass caudally and have a spinal outflow localised around vertebra 15. Pigmento-motor fibres are then distributed to the cutaneous melanophores via the sympathetic chain, spinal and trigeminal nerves. The investigation described in this thesis is concerned with the location of the spinal pigmento-motor fibres. Mallory's trichrome, Mallory's eosin and methylene blue and Weigert Pal preparations were used to investigate the anatomy of the spinal cord of the minnow. Comparisons are made with the spinal cord of some other teleosts and literature concerning the functions of teleost spinal tracts is reviewed. Microdissection instruments were used to place lesions at vertebrae 3, 4 and 10 and around the spinal outflow. A study of the effects of such lesions upon the responses to black and white background reversal was coupled with a histological examination of the lesions. Such studies indicate a spinal location of the pigmento-motor fibres in the area of the dorsal horns and corpus commune posterius at vertebrae 3, 4 and 10. Complete spinal lesions indicate that the pigmento-motor outflow levels occur between vertebrae 12 and 14, somewhat cephalic to those in von Frisch's mid-European specimens. Cutting some of the spinal pigmento-motor fibres results in differential behaviour of the melanophores, producing a bilateral, dorsolateral cutaneous mottled pattern in response to background reversal. It would appear that the fibres of any specific region of the spinal pigmento-motor tract are associated with melanophore innervating fibres having a wide cutaneous distribution. The melanophore innervating fibres of any specific segment also appear to be associated with spinal outflow nerves of more than one of the spinal levels 12 to 14. It is suggested that postganglionic pigmento-motor fibres retain their integrity rather than form a continuous diffuse cutaneous nerve net.

While the positional relationships of the mammalian carpal bones were fully discussed by palaeontologists around 1900, the dynamic role of the carpus has been almost ignored. The roles of the forelimb in locomotion and of the carpus within the forelimb are briefly considered. There is a tendency for the wrist to be rigid during retraction, in contrast to the activity of the tarsus, and it acts as a hinge only when the limb is off the ground, folding the limb during protraction. The position close under the mid-line in which the feet are placed is emphasised, since this means that the lower limb segments must swing out sideways to pass the contralateral limb. Some ulnar deviation must accompany flexion at the carpus to achieve this. The form and function of the carpus in various groups of mammals is examined. Function is determined largely by manipulative studies, and described as degrees of flexion and deviation at the two main carpal joints. Thus in Carnivora, the proximal joint is both the main flexion hinge and a deviational joint, while the mid-carpal joint is solely a flexion hinge. In these and many other quadrupedal mammals with proximal joints of similar function, the scaphoid and lunar bones of the primitive carpus are fused. In ungulates, both joints are solely flexion hinges, and the bones of the proximal row must remain separate to provide the twisting movement which gives the deviational component. In primates both joints give moderate flexion and deviation. The isolated position of the Monotremes is emphasised.

My aim was to resolve the taxonomy of the South African forms of Cercopithecus albogularis by exploring morphological and genetic variation in the two samango subspecies described for the region: C. a. erythrarchus and C. a. labiatus. In addition, I estimated their geographic distributions and habitat requirements from the provenance data I collected during my study of museum specimens. My analysis has shown clear morphological differences between C. a. labiatus and C. a. erythrarchus. The two subspecies differ in pelage coloration, but also in cranial shape and tail lengths. Furthermore, C. a. labiatus is slightly smaller, shorter-tailed and stocky compared with the long-tailed slender northern forms of C. albogularis, which may be adaptations to cold environments like montane forest. The northern C. albogularis subspecies are distinguishable from the southern taxa with a high degree of reliability (98.5%), suggesting that C. albogularis consists of more than one species. The most appropriate name for the southern species is C. labiatus. My genetic study did not detect variation among the 10 animals sampled in Hogsback; while it clustered the different taxa, it could not resolve relationships between them, with the exception of the outgroup. The lack of resolution of the deeper nodes could be a result of the fact that our sequence was very short (274 bp). The mt 12S rRNA gene was not an ideal gene for this study, which should have involved a less conserved section of the mtDNA molecule, like the rapidly evolving D-loop. More genetic work is clearly needed to resolve the phylogenetic relationships within the C. mitis supergroup. However, preliminary genetic data indicate that the southern samangos are distinct from the C. mitis of West Africa, while my morphometric study suggests they may also be distinct from C. albogularis in East Africa. Molecular and karyological studies comparing the genomes of Hogsback “C. a. labiatus” with the neighbouring “C. a. erythrarchus” and Zanzibar C. albogularis would be extremely enlightening.

The nine amino acid peptide vasopressin acts as a neurohormone in the periphery and a neurotransmitter/neuromodulator in the central nervous system. Historically, research on vasopressin neurons and their projections to the pituitary has helped lay the groundwork for our understanding of peptidergic neurotransmission. Currently, our research on central vasopressin projections is driving a revolution in our understanding of social behavior. Vasopressin affects a number of social behaviors from social memory to aggression to affiliative behavior, such as pair-bonding. Further, with the addition of more and more transgenic mouse models of disease states, anxiety and depression related disorders, and social behavior dysfunction, it is important now more than ever to have a clear knowledge of the mouse vasopressin system, which derives from a number of distinct nuclei within the brain. Here, I map out vasopressin immunoreactivity in the mouse brain, and delineate the subset of brain regions with gonadal steroid hormone-dependent vasopressin immunoreactivity. Such projections are thought to derive from the bed nuclei of the stria terminalis and medial amygdala in the telencephalon. Finally, based on data from mice with lesions of the suprachiasmatic nucleus, I outline the subset of regions that likely receive vasopressin from this source. Our research on the anatomy of the vasopressin system of mice and our attempts to delineate the site of origin of the many vasopressin fibers found throughout the brain suggest that a significant amount of the vasopressin innervation deriving from cells in the bed nuclei of the stria terminalis and medial amygdala project to areas in the midbrain involved in serotonin and dopamine transmission, such as the dorsal raphe and ventral tegmental area. These transmitter systems play a crucial role in the control of anxiety and depression levels as well as motivated behavior and emotional regulation. Our results strongly suggest that a direct link exists between these systems, and future plans include an examination of this possibility. It is our hope that this work will further our understanding of the role of vasopressin and other transmitter systems in the regulation of social behaviors.

The omentum has, from time to time, provoked sporadic reports on various aspects and, occasionally, a series of reports on one in particular. Hitherto no comprehensive account of the omentum and its function has been given. This thesis was undertaken with a view to correlating the available information and, in addition, performing further investigations along lines that were indicated. The Anatomy and Comparative Anatomy has received scant attention and the question of independent movement by the omentum has not yet been satisfactorily settled. These subjects have, therefore, been investigated and reported on at some length. In addition, some experiments of other observers have been repeated and a few original observations have been made and their significance discussea.

In the human species as in all the animal kingdom considerable individual variation is encountered, differences being seen in morphology, size, activity, and in reaction manifests itself in differing susceptibility to disease and to the effects of injury; an epidemic causing an individual to succumb while another escapes, one dies from a trivial electric shock while another survives contact with a high voltage. The factors known to be involved in this variability of response includes race, heredity, nutritional state, climate, social environment, psychological outlook and bodily morphology. The gross anatomy of certain organs of the body such, for example, as the endocrine glands has a little or no relation to their fundamental efficiency, so that the thyroid gland would probably produce its secretion equally well were it of a different shape or situated in another part of the body.