239 Dominican Fossils — Maury 75 



ing ridges. A decollate shell measures 63 X 13 rnm. We have 

 metatypes from Gabb for comparison with our own specimens. 

 The species has been also found at Gatun. 



Localities. — (Exp'd '16) Bluff 1, Cercado de Mao; Zone I, 

 Rio Cana at Caimito. 



Mitra quemadica, n. sp. 

 Plate 11, Figure 12 



Shell fusiform, biconic, suture indistinctly bordered by a 

 sub-nodulose band; entire surface ornamented with revolving 

 cords, five on the penultimate, and fifteen on the ultimate 

 whorl; these cords are equidistant except just below the suture, 

 where the interspace is double the normal; they are crossed by 

 much weaker longitudinal growth -lines; aperture elliptical; col- 

 umella with three strong posterior folds and one faint anterior 

 one; margin of outer lip serrate. Length 28, width 11 mm. 



In some respects this shell agrees with Gabb's description of 

 his unfigured M. rudis, but our shell is narrower and has many 

 instead of a few revolving spirals. 



Locality. — (Exp'd '16) Zone D, Rio Gurabo at Los Ouemados 

 (Rare). 



Mitra titan Gabb 



Plate 11, Figures 14, 14a ( 



Mitra titan Gabb, Trans. Amer. Phil. Soc, vol. 15, p. 220, 1873. 

 Mitra titan Dall, Trans. Wagner Inst. Sc, vol. 3, pt. 1, p. 94, 1890; 

 pt. 2, p. 229, 1892. 



This shell is strikingly like the Jacksonian Eocene M. Milling - 

 toni, but the latter is slenderer with a more elongate last whorl. 

 Doubtless the Dominican shell is the descendant of the earlier 

 species which lived in the Mississippi embayment. We have a 

 metatype of M. titan. The type measured 152X45 mm. Gabb's 

 M. symmetricus may be the young of titan. 



