TORNATELLINA. 133 



thin, simple; the palatal wall either smooth, toothed or lam- 

 inate. Reproduction viviparous. 



Type, T. clausa = bUamcllata. Distribution, Islands of the 

 Pacific, East Indies. 



Tornatellina is now restricted to imperf 'orate species. The 

 allied umbilicate forms are placed in the genera Tornatellides 

 and Tornatellaria, and the genus Elasmias is instituted for 

 the globose forms with truncate columella. 



Nomenclature. 



Tornatellina was instituted by Beck (Index Mottuscorum, 

 1837, p. 80) for four species, all new, and none of them de- 

 scribed. 



"1. T. clausa B., I. Opara. 



"2. T. trochiformis B., I. Juan Fernan. 



"3. T. trochlearis B., I. Mapasuera [Masafuera]. 



"4. T. archimedis B., I. Opara. 

 "a. major, 

 "b. minor." 



Since neither the genus nor any of the species were denned 

 by a single word, Beck's action was ineffective. His nomina 

 nuda in no way prejudice subsequent work on either genus or 

 species. 



Pfeiffer, in the Symbolcc ad Historiam Heliceorum, ii, 1842, 

 defined the genus Tornatellina Beck (p. 5), and described the 

 following species (p. 55) : Tornatellina clausa Beck, T. minuta 

 Ant., T. trochiformis Beck, T. trochlearis Beck. On p. 130 he 

 gives a list of the known species : Archimedis B. (= turrita) , 

 clausa B., cubensis Pfr. (=Achatina pellucida Pfr., 1840), 

 fentssaci Pfr., minuta Ant., ovata Ant., owaihiensis Cham., 

 trochiformis B., trochlearis B. 



This is the first publication of Tornatellina which can be 

 recognized in nomenclature. Gray, in 1847, selected T. clausa, 

 the first species of Beck's and Pfeiffer 's lists, as the type. 

 This species has been considered by Pfeiffer to be synonymous 

 with T. bilamellata Anton. The subsequent selection of tro- 

 chlearis as type, by von Martens (Die Heliceen, 1860, p. 259), 

 was ineffective on account of the prior selection of T. clausa 

 by Grav. 



