The Third Eye

activity amphibian Anguis fragilis animals anlagen ascidian axoneme axons blue-bellied brain capsule cavity centriole chromatic cilia ciliary cilium connecting piece cornea cross section cytoplasm disks doublets Eakin and Brandenburger Eakin and Westfall electron microscopy embryonic epiphysis eye of lizards eye of Sceloporus fence lizard Ferlatte frog frontal organ function ganglion cells gland glycogen Heretofore unpublished inner segment lampreys lateral eyes light light-sensitive lumen median eye Meiniel membrane microscope microtubules mitochondria nerve fibers neural Nowikoff nuclei ocellus Oksche outer segment parietal eye parietal foramen parietal nerve parietal organ parietal vesicle parietalectomized photopigment photoreceptors pigment granules pigmented cells pineal and parietal pineal body pineal diverticulum pineal eye pineal foramen pineal organs pineal vesicle Rana receptor cells receptoral process reptiles responses retina ribosomes rods and cones Sceloporus occidentalis sensory cells skin Stebbins and Eakin stirnorgan structure supportive cells synaptic ribbons tadpole third eye thyroid tridentatus vertebrates wavelengths Zool