• Specular microscopy of the in vivo corneal endothelium of 48 clinically normal eyes of 31 infants less than 1 year old revealed a regular mosaic of small cells. The cell population density of individuals varied greatly, as it does in age-related adults. Reexamination of five eyes indicated a reduction of the cell population density during the first year. This change could be accounted for by corneal growth in the absence of endothelial mitoses and not necessarily by true cell loss. There were morphologic indications of mitoses, but their interpretation is open to doubt.