The Parietal Eye (PE) is present in the amphibian and reptilian, by contrast PE is lost in the bird and mammaliam. PE is a part of the pineal complex and still it is dubious the its embryological origin. This study on the a reptilian Chalcides ocellatus shows that the PE originates from the a single vesicle; early the apical part of the vesicle differentiates into PE and successively lost the connection with the basal part of vesicle that differentiates into epiphysis. Histological structure PE differentiates into lens with elongated cells and retina with the photoreceptors or sensitive, radial cells, ganglion cells from which the nerve originates and pigment cells. Both the different development and histological architecture than the lateral eye suggest that the function of PE is limited to the perception of light and heat intensity since the pigment migrates according to different light and thermal conditions.
A. Gerbino, L. Lipari, E. Farina, F. Carini and A. Lipari. The Parietal Eye in Reptile, Chalcides Ocellatus: An Embryological and Histological Study.
DOI: https://doi.org/10.36478/vr.2015.27.31
URL: https://www.makhillpublications.co/view-article/1993-5412/vr.2015.27.31