314 CALIFORNIA ACADEMY OF SCIENCES. 



suture impressed, distinct; aperture semilunar; outer lip sharp; inner lip callous and reflected 

 completely over the umbilicus. 



Dimensions. — Alt. 27 mm.; lat. 25 mm.; aperture 20 mm. x 12.5 mm.; defl. 115 degrees. 



After comparing a series of Naticas collected from the Pliocene of Deadman 

 Island, part of which were identified as A^ russa and part as N. chiusa by Dr. Dall, 

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

 is distinguishable from Neverita recluziana by a more elevated spire, more evenly 

 convex whorls, and a more concave umbilical region. 



Rare in Pliocene of Deadman Island and Tiram'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 

 Hill, and in the Pleistocene at the bath-house, Santa Barbara. The 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 Montfovt. 



This group includes all of the Naticithe with corneous opercula. 

 Type, JSfatica 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 dwplicata Say is a characteristic species. 



354. Polynices (Neverita) recluziana Petit. 

 PL.VTK X, Fic. 12. 



Natica recluziana Petit, Deshayes, 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. 20S, 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. 2X1. 

 Neverita recluziana Desh., Gabb, Pal. Cal., Vol. II, \>. 77, 1869. D.\ll, Trans. Wagner Inst. Sci., 



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



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

 slighdy convex; body-whorl having a long, slightly convex slope fi-oni suture to near base, where it 



