n8 Bulletin 29 



the other; aperture narrow widening very slightly anteriorly. 

 Length 8, width 5.50, altitude 5 mm. 



The fossils differ from T. suffusa, now living in the Antilles 

 and fossil at Bowden, in their more convex form and narrower 

 and straighter aperture. 



Our three species of Trivia are the first ever found in the 

 Santo Domingo blue clays. 



Locality. — (Exp'd '16) Bluff 3, Cercado de Mao. (Rare). 



Genus Erato Risso 



Erato Mangerice variety doming e?tsis, n. var. 



Plate 21, Figure 8 



Shell minutely ficiform, whorls three, suture indistinct, spire 

 very short, obtuse, last whorl very globose posteriorly, contracted 

 and slightly produced anteriorly; aperture linear, nearly as long 

 as the shell, margin of outer lip much thickened, minutely crenu- 

 lated within; inner lip perfectly smooth except for a longitudinal 

 ridge. Length 4, width 3.25 mm. The species differs from E. 

 Maugeria, which we collected on the Monte Cristi beach and is 

 found as a fossil at Bowden, in the following respects: — it is 

 smaller, more contracted and produced anteriorly, the inner lip is 

 smooth and has the longitudinal ridge, while the inner lip of the 

 recent shell has no ridge but a dozen sharp denticles extending its 

 entire length. 



Locality. — (Exp'd '16,) Bluff 3, Cercado de Mao. 



Genus Strom bus Linne 

 Strombus haitensis Sowerby 

 Plate 20, Figure I 

 Strombus haitensis Sowerby, Quart. Jour. Geol. Soc. London, vol. 6, 



p. 48, pi. 9, fig. 7, 1849. 

 Strombus bituberculatus Gabb, Trans. Amer. Phil. Soc, vol. 15, p. 233 



1873. Not bituberculatus Lamarck. 

 Strombus haitensis Guppy, Quart. Jour. Geol. Soc, vol. 32, p. 521 



1876. 

 This species differs from kS". bituberculatus, of which we found 

 beautiful shells on the Monte Cristi beach, in the following re- 



