36 Proceedings of the Biological Society of Washington. 



of the shell. The pits enclosed by the spiral cords and axial ribs are well 

 rounded on all the whorls. Suture strongly impressed. Periphery of the 

 last whorl marked by a sulcus about as broad as that separating the median 

 from the supersutural cord on the spire. Base short, well rounded, marked 

 by feeble continuation of the axial ribs, which lend it a roughened aspect, 

 and a single slender spiral thread, which encircles the base at the insertion 

 of the columella. Aperture decidedly channeled anteriorly; posterior angle 

 obtuse; outer lip thin, showing the external sculpture within, sinuous at the 

 edge; inner lip sigmoid, reflected over and appressed to the columella. 



The type, Cat. No. 340,827, U. S. N. M., was collected by Mrs. Oldroyd 

 in 20 fathoms, off O'Neal Island, Puget Sound. It has almost seven post- 

 nuclear whorls and measures: length, 5.1 mm.; diameter, 1.9 mm. 



Cerithiopsis (Cerithiopsina) signa, new species. 



Shell elongate conic, pale brown. First half postnuclear whorl smooth, 

 the next one and a half well rounded and marked by rather distantly spaced, 

 almost vertical axial ribs. Postnuclear whorls appressed at the summit, 

 marked by strong, rounded almost vertical axial ribs, of which eighteen 

 occur upon the first, fourteen upon the second to sixth, sixteen upon the 

 seventh, and eighteen upon the last turn. The spiral sculpture consists of 

 three strong, equally spaced cords, which are crossed by strong axial ribs. 

 The intersection of the axial ribs and the spiral cords form strong tubercles, 

 which are truncated on their posterior margin, and slope gently anteriorly 

 in all three groups. The spaces enclosed between the cords and the ribs 

 are elongated pits which have their long axis coinciding with the spiral 

 sculpture. In addition to this, the entire surface of the spire is marked by 

 fine axial lines of growth and closely spaced spiral striations. Suture 

 strongly impressed. Periphery of the last whorl rendered angulated by a 

 keel. Base short, slightly concave at the insertion of the columella, marked 

 by fine lines of growth and very fine spiral striations, and a slender spiral 

 thread at the insertion of the columella. Aperture subquadrate; decidedly 

 channeled anteriorly; posterior angle obtuse; outer lip rendered sinuous 

 by the spiral cords; inner lip sigmoid, reflected over and appressed to the 

 columella. 



The type, Cat. No. 340,826, U. S. N. M., was collected off O'Neal Island, 

 Puget Sound. It has 10.5 whorls and measures : length, 5.5 mm. ; diameter, 

 2.7 mm. 



The following additional specimens have been examined: 3 specimens, 

 Nanaimo, British Columbia, Cat. No. 340,841, U. S. N. M. 4 specimens, 

 Port Orchard, Puget Sound, Cat. No. 133,233, U. S. N. M. 7 specimens, 

 San Juan Island, Puget Sound, Cat. No. 340,934, U. S. N. M. 



Cerithiopsis (Cerithiopsina) willetti, new species. 



Shell large, robust, elongate conic, pale brown. All but the last nuclear 

 whorl decollated. This shows, however, that the species belongs to the 

 subgeiuis Cerithiopsina. Postnuclear whorls crossed by very strong, almost 

 sublamellar, rather coarse, rounded, protractively slanting axial ribs, of 

 which sixteen occur upon the first to fifth, eighteen upon the sixth, twenty 



