American opisthobranch mollusks

In 1963, a series entitled Studies in Tropical Oceanography was established at the institute of marine sciences to include major papers in the marine sciences which cannot be accommodated in journals because of their size. The editors now take great pleasure in presenting as the sixth volume in this series a major contribution to the knowledge of the marine mollusks of American waters. Under the general title "American Opisthobranch mollusks," By Eveline du Bious Reymond Marcus and Ernest Marcus of the University of Sao Paulo, Brazil, this volume compromises two parts. The first deals with tropical American opisthobranchs, from Florida to Brazil and including material from the faunistically related bay of panama, and the second with species from the gulf of California. A total number of 111 species and subspecies (70 in part 1, 47 in part 2, with six common to both) is reported and for the most part described in full and illustrated. Not until now has knowledge of the opisthobranch fauna of the western Atlantic reached the level of that of the shelled molluscan groups, which considered to be on the whole well known as early as 1910. The opisthobranchs of the gulf of California must still be considered incompletely known even after the present study, as sampling has been inadequate in that large and environmentally diverse body of water.