THE BRYOZOAN FAUNA OF THE GALAPAGOS ISLANDS By Ferdinand Canu Of Versailles, France AND R. S. Bassler Of Washington, District of Columbia. INTRODUCTION Continuing our investigations of the dredgings of the United States Fish Commission steamer Albatross preserved in the United States National Museum, we have recently completed the study of the material collected from a few stations in the vicinity of the Galapagos Islands. As a result we find that the bryozoa of the Galapagos afford equally interesting results as other classes of animals from this classic area. In the pursuit of these studies we have had financial assistance from the American Association for the Advancement of Science, which help is here gratefully acknowledged. Located on the equatorial line, the bryozoan fauna of the Galapagos Islands is found to be particularly interesting to the paleontologist. The species common with the Gulf of Mexico indicate the ancient communication of the Pacific with the Atlantic and the very recent formation of the Isthmus of Panama. These species are Acantho-desia savartii, Aplousina fZum^ Callofora tenuirostris, Calloipora curmrostris^ Cwpuladria umhellata^ Puellina innominafa^ Trypostega venusta, Hippoporina deidostoTna, Mamillopora cuptila, and Liche-nopora radiata. None of these is known to have made the circuit of any of the continents, so that free communication between the two oceans must have existed. Another remarkable phenomenon is the persistence in this region of archaic forms laiown hitherto only as fossils and in which nat-urally the anatomic structure was unknown. Very useful compari-sons can thus be made by means of such species as Probosdna lamel-lifera, Plagioecia subpapyracea^ Diaperoecia {ReticuUpora) mean-No. 2810.— Proceedings U. S. National Museum, Vol. 76, Art. 13. 61589—29 1 1
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