Fossil species of Conus from the southeastern United States and Caribbean areas never before have been studied systematically. Previously recorded Conus occurrences have appeared only as parts of faunal lists from certain localities. Thus, the resulting number of synonyms and inaccurate identifications have increased through the years.

Because no study of the relations between described species, horizontally or vertically, has been made, this study was undertaken to evaluate and to revise the nomenclature of fossil cones from numerous localities in the southeastern United States and Caribbean regions. The extensive collections of Cenozoic mollusks at Tulane University provided much of the material studied, supplementing field collections made by the writer. Several institutions, including the United States National Museum, the Academy of Natural Sciences at Philadelphia, and the Paleontological Research Institution, kindly have loaned type specimens.

More detailed study of this genus reveals that some forms designated as different species actually are variations of the same species. Morphological variability studies for the shells of each locality are being made. Ecology, where appropriate, is correlated with the morphological data. A new technique, the relation of color patterns on fossil shells to the morphological features, is used. The method for partly restoring color to fossils has been developed recently by Axel A. Olsson. Shells oxidized either artificially or by exposure to the sun exhibit their definitive color patterns clearly under ultraviolet light. Although the color of a shell may vary within a population, depending on its environment or diet, the basic patterns of dots in spiral rows, tent shapes, bands, or reticul tions are fixed for a given species. The color pattern is produced by the arrangement of excretory glands in the mantle, and as such is a physiological feature and, therefore, a record of the soft parts of the animal.

Intensive study of one genus, with regard to its position in time and its distribution in space, helps resolve some of the taxonomic problems. Because Conus has a wide distribution (tropical Atlantic, Pacific, and Indian Oceans, and their associated seas), an efficient study must be limited geographically. With the several techniques discussed, and the large collections and many references at hand, the more accurate classification of this genus is achieved.

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