Abstract: Process and apparatus for photoaccelerating the development of eggs such as chicken eggs. The eggs are arranged in an incubator such that the air cells thereof are disposed upwardly. During incubation the eggs are exposed to radiation in the visible spectra through the air cell during the period of buoyancy of the embryo. Preferred regions of the spectrum are the blue region, red region and yellow region. The apparatus of the invention provides for the transmission of light by fiber optics to the air cell region of each egg from light sources disposed adjacent egg carrying racks within the incubator.