!7i Dominican Fossils — Maury 107 



Genus Gutturnium Adams 



Guttumium gracile variety gurabonicum, n. var. 

 Plate 17, Figure 10 

 Cf. Triton gracilis Reeve, Conch. Icon., fig. 58 a, b. 

 Shell resembling specimens of G. gracilis Reeve, living in 

 the Antilles, but with more prominent dorsal humps, shorter 

 canal, and surface much more finely reticulated. Length of de- 

 collate shell 23, width 12 mm. 



This shell has some resemblance to Gabb's Triton domin- 

 gensis (See Guppy's figure, Quart. Jour. Geol. Soc, vol. 32, pi. 

 29, fig. 2) but that species has an elongate aperture and nearly 

 straight canal while ours has a round aperture and sharply twis- 

 ted canal. 



Locality. — (Exp'd'16) ZoneD, Rio Gurabo at Los Quema- 

 dos. 



Genus Distortrix Link 



Distortrix simillima Sowerby. 

 Plate 17, Figures 4, 5 



Triton simillimus Sowerby, Quart. Jour. Geol. Soc. London, vol. 6, 



p. 48, 1849. 

 Persona simillima Guppy, Quart. Jour. Geol. Soc. vol. 22, p. 288, pi. 



17, fig. 13, 1866. 

 Distortia simillimus Gabb, Trans. Amer. Phil. Soc, vol. 15, p. 212, 



1873. 

 Persona simillima Guppy, Geol. Mag. London, p. 439, 1874: Quart. 



Jour. Geol. Soc, vol. 32, p. 522, 1876. 

 Distortrix simillima Dall, Trans. Wagner Inst. Sci., vol.3, pt. 6, p. 



1584, 1903- 

 Distorsio {Distortrix, Persona) gatunensis Toula, Jahrb. der K. — K. 



Geol. Reichsanstalt Wien, vol. 58, p. 700, pi. 25,. fig. 10, 1908. 

 Distorsio gatunensis Brown and Pilsbry, Proc. Acad. Nat. Sci. Phila., 



p. 356, pi. 26, fig. 8, 1911. 



Toula' s type of D. gatunensis was an immature shell. Brown 

 and Pilsbry have figured a larger specimen which is so like some 

 of our Dominican shells that they seem entirely identical. The 

 more so, since a very fine shell we collected has the embryonic 



