BULLETIN FLORIDA STATE MUSEUM


FIGURE 4.-Scanning Electron Micrographs of North American hydrobiid snail embryonic sculp-
ture: (A) Rhapinema dacryon Thompson (UF 22378) X196; (B) Cincinnatia integra (Say) (UF
22189) X224; (C) Notogillia wetherbyi (Dall) (UF 22191) X245; (D) Marstonia hlstrica (Pilsbry)
(UF 22190) X203; (E) Marstonia ogmorhaphe new species (UF 22180) X214; (F) Marstonia arga
new species (UF 22287) X210; (G) Marstonia agarhecta Thompson (UF 20529) X224; (H) Mar-
stonia castor new species (UF 22177) X196; (I) Marstonia halcyon new species (UF 22313) X166.


Vol. 21, No. 3


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