314 CALIFOKNIA ACADEMY OF SCIENCES. 



suture impressed, distinct; aperture semilunar; outer lip sharp; inner li|) callous antl rcllcctfii 

 completely over the umbilicus. 



Dimensions. — Alt. 27 nun.; lat. 25 mm.; aperture 20 mm. x 12.5 mm.; doll. 115 dep;rei's. 



After compariiijj a scries of Naticas collected from the Pliocene of Deailmati 

 Island, part of wliieli were identified as N. russn and part as N. chmsa by Dr. Dall, 

 it is very evident that there is no difference between the two species. This species 

 is di.-;tingnishable from Neveiita recluziann liy a mure elevated spire, more evenly 

 convex whorls, and a more concave umbilical region. 



Rare in Pliocene of Deadman Island and Tinim's Point. None have been 

 found in the Pleistocene by the writer, except one small specimen which came from 

 the lower San Pedro series at Deadman Island. Found in the Pliocene at Packard's 

 Ilill, and in tiie Pleistocene at the bath-house, Santa Barbara. Tiie specimen 

 figured is a medium sized one from the Pliocene of Deadman Island, and is now in 

 the collection of Delos Arnold. 



Living. — Arctic Ocean; Alaska; North Atlantic (Cooper). 



Pleistocene. — Santa Barbara to San Diego (Cooper): San Pedro; Santa 

 Barbara (Arnold). 



Pliocene. — San Pedro; Santa Barbara (Arnold). 



Genus Polynices Muntfort. 



This group includes all of the Naticidte with corneous operciila. 

 Type, Natica mammilla Linn. 



Subgenus Neverita Risso. 



Shell depressed, orbicular; spire conical or flattened; columella partly filled by a tongue- 

 shaped callous process (funiculum) from the columella. Operculum horny. 



Natica duplicata Say is a characteristic species. 



354. Polynices (Neverita) recluziana Petit. 



rL.VTK X. Fic. V2. 



Natica recluziana Petit, Deshaves, Mag. de Zool., Mollusca, p. 37, 1841. Tryon, Man. Conch., 



Vol. VIII, p. 34, PI. XII, fig. I, 1886. 

 Neverita recluziana Petit, H. & A. Adams, Gen. Rec. Moll., Vol. I, p. 208, 1853. Cpr., Brit. 



Assn. Rept., 1863, p. 661. Cooper, 7th Ann. Rept. Cal. St. Min., 1888, p. 254. 



Keep, West Coast Shells, p. 46, fig. 26, 1892. Williamson, Proc. U. S. Nat. Mus., 



Vol. XV, 1892, p. 211. 

 Neverita recluziana Desh., Gabb, Pal. Cal., Vol. II, p. 77, 1869. Dall, Trans. Wagner Inst. Sci., 



Vol. Ill, Part 2, 1892, p. 369. 



Shell ovate to flattened globular; spire only very slightly elevated, obtuse; whorls three, 

 slighdy conve.x; body-whorl having a long, slightly convex slope from suture to near base, where it 



