EAST AMERICAN SCAPHOPOD MOLLUSKS. 129 



("1.4")- It was dredged by the Blake at the United States Coast 

 Survey Station 19, off Bahia Honda, Cuba, in 310 fathoms, bottom 

 temperature 52.25° F. 

 There are no examples in the museum collection. 



CADULUS (PLATYSCfflDES) NITIDUS, new species. 



Plate 19, fig. 9. 



1901. Cadulus amiantus Dall and Simpsox, U. S. Fish Coram. Bulletin for 1900 

 vol. 1, p. 457. 



The shell is very moderately curved, slender, with its section of 

 greatest diameter at about the oral third. There being no local swell- 

 ing or bulging, the exact position of the equator is not clearly marked. 

 The convex side shows an even uninterrupted arc. The concave 

 side is almost a straight line with some slight curvature at the pos- 

 terior end and with scarcely any convexity at the equator. The shell 

 is round in section, there being no flattening at any point; viewed 

 ventrally, the lateral lines converge but gradually from the narrow 

 equator to a rather large apical orifice and to a relatively small 

 anterior aperture. The last is but slightly oblique. The apical 

 characters are very distinct, showing four shallow but well-marked 

 notches separating as many lobes, the dorsal and ventral ones being 

 the widest. Within the apical orifice is an opaque ring, though this 

 may not always be present. 



The type, Cat. No. 161582, (a), U.S.N.M., measures— length, 5.75 

 mm.; diameter, 0.9 mm.; anterior aperture, 0.75 mm.; apical aper- 

 ture, 0.5 mm. It was collected at the U. S. B. F. Station 6062, in 

 Mayaguez Harbor, Porto Rico, in 25 fathoms, bottom of sand, mud, 

 and shells; temperature, 75.8° F. It is selected from a lot of 40 

 specimens. 



These shells were originally identified as C. amiantus, but compari- 

 son with the type obliges me to remove them. They are smaller and 

 more slender than are any other species placed near them in this 

 review; these specimens show the apical features with the perfect 

 definiteness of some species of Polyschides. C. nitidus is smaller than 

 0. portoricensis, but otherwise very closely related. 



CADULUS (PLATYSCHroES) MUMIENSIS, new species. 



' Plate 19, fig. 18. 



The shell is rather strongly curved; the convex outlme describes 

 a fairly even arch, though flattened in its anterior portion between 

 the aperture and the equator. The concave outline is more arched 

 posteriorly though it is not quite a straight line from the equator to 

 the aperture. The maximum diameter is about two-fifths distance 

 from the anterior aperture. There is no local bulge nor swelling nor 



