For the reason that no records for this group of animals have been made anywhere near that region, the Bryozoa collected by Dr. C. J. VAN DER HORST are of great interest. The collection is quite limited in the number of species, as might have been expected on account of the inconspicuous nature of most of them. Only the specialist in the group, accustomed to collect these minute animals and familiar with their habits of growth, occurrence and appearance, need ever expect to take a very complete series of them. Most of the species in the collection appear to be there incidentally, attached to shells, corals, etc., and were later found on close inspection. A considerable number of the species are represented by only one or two specimens and the examination of debris under the binocular microscope yielded several species in the form of minute portions of colonies. No doubt the bryozoan fauna of the waters about Curaçao includes several times as many species as appear in this report. It is a typical collection of the tropical seas as far as it goes. Most of the species represented here are found in the Florida waters, where they have been recorded by SMITT (1872—73) and OSBURN (1914). LEVINSEN (1909) has listed incidentally a few of the species for the region about the Virgin Islands (at that time the Danish West Indies). Otherwise, practically nothing is known of the Bryozoa in all that vast region which includes the West Indies, the Caribbean Sea and the Gulf of Mexico.