Michel Lemire

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The retinofugal projections of 5 species (Acanthodactylus boskianus, Scincus scincus, Tarentola mauritanica, Uromastix acanthinurus and Zonosaurus ornatus) belonging to 5 different families of Type I and Type II lizards have been examined by means of the radioautographic method. In the 5 species the retinal ganglion cells project to the contralateral(More)
The published descriptions of ipsilateral visual pathways in non-eutherian species are reviewed. Such pathways exist in members of all vertebrate classes; since they exist in agnathans, it is suggested that the presence of ipsilateral visual projections is the ancestral condition. None of the published attempts to explain the considerable interspecific(More)
The development of the primary visual centres was studied in a series of embryos of the turtle, Emys orbicularis, incubated at 25 degrees C. The differentiation of both visual and nonvisual diencephalic and mesencephalic structures takes place entirely within the 2nd quarter of the period of incubation; this finding appears to be consistent with previous(More)
A quantitative investigation of the optic nerves of eight adult vipers was carried out, both at the level of resolution of the light microscope by stereological methods, and at the level of resolution of the electron microscope. The majority (87%) of axons are myelinated, and the fibers are organized in fascicles; each bundle of axons is disposed around a(More)
The retinocerebral projections of Emys orbicularis were investigated by means of [3H]-proline or HRP, administered by intraocular injection. Two newly-hatched, two juvenile and seven adult specimens were examined. The results reveal contralateral retinal projections to fifteen sites: two in the hypothalamus (the nuclei suprachiasmaticus and(More)
The primary visual system of 21 species of turtles, distributed among nine of the existing 12 families, were studied by autoradiography. In all species, contralateral visual projections exist to 15 targets: two hypothalamic structures (nucleus suprachiasmaticus and n. periventricularis), three major thalamic visual centres (nucleus ovalis, n. geniculatus(More)
The retinal projections of three species of cyprinid fish (Cyprinus macrolepidotus, Cyprinus carpio, Rutilus rutilus) were examined with Nauta and Fink-Heimer methods following enucleation and with radioautography following intraocular injection of [3H]-L-proline. Optic tract axons cross completely in the optic chiasma and are distributed to the(More)
The optic nerve in two species of subterranean mole-rats (Spalacidae) has been examined at the ultrastructural level. The axial length of the eye and the diameter of the optic nerve are 1.9 mm and 52.5 microns in Spalax leucodon, and 0.7 mm and 80.8 microns in Spalax ehrenbergi, respectively. An anti-glial fibrillary acidic protein postembedding procedure(More)
The ultrastructural changes taking place in the retino-recipient layers of the viper optic tectum were examined between 5 and 122 days after retinal ablation. The initial degeneration of retinotectal terminals proceeds at widely different rates and is characterized by a marked degree of polymorphism in which a number of different patterns can be discerned.(More)