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Dall
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serial sent to the Smithsonian Institution, some years ago, by Dr. J. J. Brown of Sheboygan, Wis from Watling Id, Bahamas; another small lot from the same place, collected by the U. S. Fish Comm., and a third lot collected by Alexander Agassiz. The lagoon species are peculiarly thin, small in size and, when colored, quite brilliant. Notes are given on 12 marine and 16 land species and varieties, of which 5 are new. The genus Cerion (formerly called Strophia) is divided into subgenera founded on characters of the internal laminae. 

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The mechanical cause of the folds in the aperture of the shell of Gasteropoda, by Wm. H. Dall. [American Naturalist XXVIII, Nov. 1894, pp. 909-914, figs. 1-3.] 
Adapted from the Transactions of Wagner Free Institute of Science, III, 1890, p.58. Dr. Dall shows that in those Gasteropods which have plicate apertures the adductor muscle, which is attached to the columella, is placed deeper within the shell than in the non-plicate forms; that, in certain cases, the body of the animal covered with its mantle is compressed as it is being drawn into the shell and therefore longitudinal wrinkles are formed in the mantle. The secreting surfaces deposit shelly material, which in the folds, takes the form of ridges in the aperture of the shell.

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Contributions to the Tertiary fauna of Florida, with especial reference to the Miocene silex beds of Tampa and the Caloosahatchie River. Part III- A new classification of