i24 Bulletin 29 



row of tubercles. It has somewhat the aspect of C. atratum liv- 

 ing on the Monte Cristi beach. 



Our shell is named in honor of Hon. W. W. Russell, M. P.. 

 E. E., American Ambassador at Santo Domingo City, as a slight 

 recognition of his very kind interest in our expedition. 



Locality. — (Exp'd'i6) ZoneD, Rio Gurabo at Los Quema- 

 dos. 



Cerithium uniseriale Sowerby 

 Plate 21, Figures 14, 15 



Cerithium uniseriale Sowerby, Quart. Jour, Geol. Soc. Loudon, vol. 6, 



p. 51, 1849. 

 Cerithium obesum Gabb (in part), Trans. Amer. Phil. Soc, vol. 15, 



p. 237, 1873. 

 Not Cerithittm uniseriale Gabb, Id. p. 237. 1873. 

 Cerithium uniseriale Guppy, Quart. Jour. Geol. Soc, London, vol. 32, 



p. 519, pi. 29, fig. 4, 1876. (Figure of Sowerby's type). 



The true C. uniseriale Sowerby, based on Guppy 's figure of 

 the type, can always be recognized by its short, broad form, 

 sudden ascent of the body whorl near the aperture, and tubercu- 

 lated whorls. It has also been found at Cumana. 



Localities. — (Exp'd '16) Zones B and D, Rio Gurabo at 

 Los Ouemados; Bluff 2, Cercado de Mao. 



Cerithium obesum Guppy 

 Plate 21, Figure 16 



Cerithium obesum Gabb (in part), Trans. Amer. Phil. Soc, vol. 15, p. 



237, 1873. 

 Cerithium obesum Guppy, Quart. Jour. Geol. Soc. London, vol. 32, p. 



519, pi. 29, fig. 9, 1876. 



Gabb's C. obesum included C. tmiseriale Sowerby (not Gabb) 

 and obesum Gabb. The species is here limited to Guppy' s re- 

 stricted sense. 



Cerithium gitrabense, n. sp. 



Plate 22, Figures 4, 5 

 Cerithium uniseriale Gabb, Trans. Amer. Phil. Soc, vol. 15, p. 237, 



i873- 



