It proved impossible to present all the animals suitable for an aquarium in one volume. Therefore, we presented certain fish families, such as the surgeonfishes and wrasses, as completely as possible, since there is no complete reference of them. This means that even fishes unsuitable for an aquarium are included, but they are clearly marked as such. However, the taxonomist will enjoy their listing. The great majority of the pictured fishes can be housed with invertebrates. The crustacea and the anthozoans are presented here. In the plant section, W. A. Tomey from the Netherlands presents an elaborate treatise on a great variety of Caulerpa. Since these higher marine algae are an almost indispensable part of the biological cycle and green decoration, the chapter on marine algae is quite extensive. Softcover, 1216 pages.