The Liverpool Marine Biology Committee was formed in March, 1885, for the purpose of investigating thoroughly the Fauna and Flora of Liverpool Bay and the neighbouring parts of the Irish Sea. The aim of the Committee is not merely to draw up an accurate list of the species found in this locality, but also to observe and record the relative numbers, the size, the colours, and the condition generally of the specimens, the exact localities in which they are found, the other species of animals and plants associated with them, and their mutual relations as food, enemies, or competitors. In this way it is hoped that a mass of observations will be accumulated which may be of use in determining the geographical distribution of various forms, the nature of the conditions which influence species, and the relations existing between the different plants and animals. It was felt at the outset that this work was exactly that department of biological investigation which could be best carried out by an organised body of workers who would subdivide the area to be investigated, and the groups of animals and plants to be worked up between them, and would carry on systematic observations year after year, sending in periodic reports upon their work. The value, in fact the absolute necessity, of this organisation, division of labour, and systematic arrangement, for the successful accomplishment of the objects in view, has been felt all along by the members of the Committee and those naturalists who have worked with them; and the results attained so far have, I think, fully justified their belief in the benefit to be derived from scientific organisation.