Vision in dim light

On testing my own vision in very dim light I observed two phenomena associated with the lack of retinal rods (the receptors specialized for vision in dim light) in the fovea, the region corresponding to our centre of gaze. First, a bright (or dark) straight line passing through the fovea was seen as discontinuous, with a clear 1° gap. Second, after adapting to dim light conditions, when I blocked light to one eye as far as possible and viewed a brightly lit surface with the other eye, I perceived a swarm of colourless scintillations throughout the visual field of the occluded eye, except for an area about 1° in diameter at the centre of gaze. Each scintillation may represent the simultaneous capture of single quanta by several closely spaced rods.