This atlas contains 189 coloured images taken from transversal, horizontal and sagittal sections of eleven organisms widely used in university teaching. Six invertebrate and five vertebrate species - from the nematode worm (Ascaris suum) to mammals (Rattus norvegicus) - are shown in detailed images. Studying the macrosections with unaided eyes, with a simple magnifier or binocular microscope might be of great help to accomplish traditional anatomical studies and to establish a certain spatial experience/space perception. This volume will be of great interest for biology students, researchers and teachers of comparative anatomy. It might act as supporting material of practical courses. Furthermore, medical practitioners, agricultural specialists and researchers having an interest in comparative anatomy might also benefit from it.