370 PROCEEDINGS OF THE ACADEMY OF [1899 



Pfr. Hitherto they have been grouped together with another 

 series of large species, of which Helix obeliscus Moric. is a typical 

 example, under the name Obeliscus Beck;^ but Gray, in 1847, 

 nominated as the type of that group the Helix obtusata of Gmelin, 

 a sj^ecies of Madagascar for which the name Clavator was subse- 

 quently proposed. Obeliscus has also been used by Humphrey* in 

 1797 as a generic name for the Trochus dolabratus of Linne, which 

 was later called Pymmidella by Lamarck. Clearly, then, we 

 cannot retain the name for these South American snails. 



In 1854, Shuttleworth' proposed the genus Stenogyra to include 

 as subgenera the prior groups Rumina Risso (1826), Obeliscus and 

 Subulina Beck (1837), Opeas Albers (1850), and the new sub- 

 genus Pseudobalea. 



These sections, as Shuttleworth terms them, are briefly defined, 

 but no types are mentioned ; after which the species of the island 

 of Porto Rico are enumerated: Stenogyra (Opeas) subula Pfr,, 

 Stenogyra (Opeas) octonoides C. B. Ad., Stenogyra (Opeas) mar- 

 g aritacea Shuttl., Stenogyra (Opeas) alabastrina Shuttl., Stenogyra 

 (Opeas) gomphorium Shuttl., Stenogyra (Opeas) Goodalli Mill., 

 Stenogyra (Pseudobalea) Dominicensis Pfr., Stenogyra (Obeliscus) 

 Swiftiana Pfr., Stenogyra (Obeliscus) terebraster Pfr., Stenogyra 

 (Subulina) octona Ch., Stenogyra (Subulina) acicularis Shuttl. 



No type species was selected, nor did Dr. von Martens name one 

 in treating of the group in the second edition of Albers' Die 

 Heliceen. It is obvious that Stenogyra cannot replace the older 

 groups mentioned above, but can only be used for some constituent 

 of the mass not already provided with a name. Such a one is 

 found in the so-called Obeliscus of Shuttleworth' s list; for, as 

 explained above, Obeliscus cannot he used in this connection. We 

 would therefore restrict Stenogyra to the Obeliscus of Shuttle- 

 worth's list, taking S. terebraster as the type. Other large Antil- 

 leau species, such as S. Salleana of San Domingo and S. gigas of 

 Cuba belong here, with probably the larger continental species 

 grouping around S. obeliscus. None -of the species are known 

 anatomically, but the small apical whorls and more numerous 

 volutions separate them from those now referred to Neobeliscus. 



^ Index Molluscorum, p. 61 (1837). 



* Museum Calonnianuin, p. 24. 



^Diag/i. Neuer Moll., No. 6, Bern. Mittheil., 1854, p. 137. 



