388 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 40. 



Shell broadly elongate-conic, rather coarse, varying in color from 

 white to chestnut brown. The nucleus consists of a single, smooth, 

 white whorl, well rounded. Post-nuclear whorls well rounded, 

 marked by four strong, somewhat flattened, spiral keels between the 

 sutures, which are separated by deep, strong, spiral grooves about two- 

 thirds as wide as the keels. In addition to this spiral sculpture, the 

 whorls are marked by numerous fine, spiral striations and fine lines 

 of growth. Periphery of the last whorl marked by a sulcus as wide 

 as the sulci between the keels on the spire. Base well rounded, 

 marked by eight equally spaced spiral cords, which grow successively 

 weaker from the periphery to the umbilical area. In addition to 

 these cords the base is marked by fine spiral lines and fine lines of 

 growth. Aperture oval, somewhat effuse anteriorly; posterior angle 

 obtuse; outer lip thin, rendered wavy by the external sculpture; 

 columella short, very broad at base, somewhat twisted and reflected; 

 parietal wall glazed with a thin callus. 



The specimen described and figured (Cat. No. 122558, U.S.N.M.) 

 has nine post-nuclear whorls and measures: Length 14 mm., diameter 

 5 mm., and was collected on the beach at Sitka, Alaska. 



Specimens examined. 



Catalogue 

 No. 



151626 

 73218 

 122558 

 195117 

 195118 

 160565 

 193687 

 195120 

 152909 

 23332 

 3935 

 5575 

 133690 

 195119 



Locality. 



Killisnoo, Alaska 



Sitka, Alaska 



Sitka, Alaska (described and figured) 



Sitka, Alaska 



do 



Biorka Island, Sitka Sound, Alaska 



Cormorant Island, Alert Bay, Alaska 



Barclay Sound, British Columbia 



Neah Bay 



do 



Puget Sound 



Puget Sound (type of Bittium filosum Gould) 



Tacoma, Washington 



Port Ludlow, Washington 



FOSSIL. 



Fossil Rock, Coos Bay, Oregon (Pliocene) 



Number of 

 specimens. 



BITTIUM (STYLIDIUM) ESCHRICHTII ICELUM Bartsch. 



Plate 57, fig. 3. 



Bittium (Stylidium) eschrichtii icelum Bartsch, Proc. U. S. Nat. Mus., vol. 33, 

 1907, p. 178. 



In B. eschrichtii only the early whorls show axial ribs. In the pres- 

 ent form they are well developed on all the turns, weakening only on 

 the last. The type, Cat. No. 15209a, U.S.N.M., was collected by 

 J. G. Swan at Neah Bay, Washington. It has nine whorls (the 

 nucleus being lost) and measures: Length 15 mm., diameter 5.5 mm. 

 Another specimen, Cat. No. 32209, U.S.N.M., belongs to the Stearns 

 collection and comes from Monterey, California. 



