. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 406 Bulletin Museum of Comparative Zoology, Vol. 141, No. 7. Figure 1. Radula of Troschelviana [Troschehiana] ery- thraea showing the central, marginal, end T-lateral teeth. 2. Radula of Trosche/v/ona [Microviana] rupes/r/s, showing central teeth and lateral T-complex (after Baker). accessory plate, which is comparatively larger than in Proserpininae, is anvil- shaped. The Vianini radula is characterized by having the typical T-lateral tooth of the Proscrpininae. The cusps on the paired central teeth as well as on the
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 406 Bulletin Museum of Comparative Zoology, Vol. 141, No. 7. Figure 1. Radula of Troschelviana [Troschehiana] ery- thraea showing the central, marginal, end T-lateral teeth. 2. Radula of Trosche/v/ona [Microviana] rupes/r/s, showing central teeth and lateral T-complex (after Baker). accessory plate, which is comparatively larger than in Proserpininae, is anvil- shaped. The Vianini radula is characterized by having the typical T-lateral tooth of the Proscrpininae. The cusps on the paired central teeth as well as on the lateral are, in general, reduced or absent. Thompson (1968: 50) wrote: "In the primitive taxa [of the Helicinidae] all of the paired cen- tral, lateral and marginal teeth have well de\elopel acuminate cusps .... The major evolutionary trend in the family is modi- fication and specialization of the capituli- form complex and simplification of the central ; This view differs from the one expressed by Clench & Jacobson (1970: 62). We felt that since tlie "smooth" radula appears in both the old and new world tropics, this type must be the more ancient. Baker (1922) separated the species of EiitwchateUa s. s. from those of TrosdwI- viana on the following radular character- istics: in Eutrochatella the single R-central rhachidian tooth is oxoid to circular in shape; in Troschelviana it is triangular ovoid to broadly elliptical. The T-latcral tooth of Eutrochatella, as well as the three paired centrals, are without cusps, or very occasionally with a single one, whereas in Troschelviana the T-lateral has five to ten cusps, and the centrals three to four each. Finally the radula of Eutrochatella has 62 to 90 marginals and 135 to 191 teeth per row; Troschelviana has 44 to 64 marginals and 99 to 103 total teeth per row. DISTRIBUTION In our arrangement of the Cuban Vianini we have made use of the cusped or uncusped nature of the radular teeth as well as certa
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