Recent Progress in Photobiology contains the proceedings of the Fourth International Photobiology Congress, held in Oxford on July 26-30, 1964 and organized by a committee set up by the British Photobiology Group. Contributors explore the developments in photobiology, particularly with respect to biological structures, chemical changes, and molecular energy. This volume is organized into 10 sections encompassing 33 chapters and begins with an overview of basic photochemical processes that have direct implications on photobiology. The next chapters discuss the photochemistry of nucleic acids and their derivatives, with some reference to their biological significance. The book also studies the visual processes in humans and animals; the structure, pigment chemistry, and function of photoreceptor systems of plant and animal cells; and receptor mechanisms in human vision. The natural photoenvironment and its influence on life and development is also explained, emphasizing how light shapes the ultimate fate of an organism in its habitat. The remaining chapters focus on energy conversion and photosynthesis; micro-irradiation of cells; photochemistry and photobiology of space research; light and melanin pigmentation of the skin; and the effect of light on plant and animal cells. This book will be of interest to biologists and physiologists, as well as to anyone engaged in photobiological research.