ARNOLD — THE PALEONTOLOGY AND STRATIGRAPHY OP SAN PEDRO. 321 



Family LXXXII. PHASIANELLID^. 



Genus Phasianella Lamarck. 



Shell elongated, polished, richly colored; whorls convex; aperture oval, not pearly; inner lip 

 callous; outer lip thin; opercuhini slielly; callous outside, subspiral inside. 



Phasianella fulimoides Lam. is a characteristic species. 



365. Phasianella compta Gvtdd. 



Phasianella compta Gld., Pac. R. R. Kept., Vol. VI, p. 333, Pi. XI, figs. 25, 26, 1857. Cpr., Brit. 

 Assn. Rept., 1863, p. 651. Gabb, Pal. Cal, Vol. II, p. 82, 1869. Tryon, Man. Conch., 

 Vol. X, p. 173, PL XXXIX, figs. 69-72, 1888. Cooper, 7th Ann. Rept. Cal. St. 

 Min., 1SS8, p. 25S. Keep, West Coast Shells, p. 89, fig. 74, 1892. Williamson, 

 Proc. U. S. Nat. Mus., Vol. XV, 1892, p. 199. 



Shell small, thin; spire elevated; apex subacute; whorls four, evenly convex; ornamenta- 

 tion consists of eight obsolete spiral ridges crossed by numerous fine oblique, incremental lines; 

 suture depressed, distinct; aperture ovate; outer lip thin; inner lip sharp and effuse, with incrustation 

 extending to umbilical region; a narrow umbilical chink is sometimes present. 



Dimensions. — Long. 9.5 mm.; lat. 6 mm. ; body-whorl 7 mm.; aperture 4.2 mm. x 2.8 mm.; 

 defl. 45 degrees. 



Distinguishable from tlie genus Lacuna by lack of distinct umbilical chink, 

 and by the spiral lines. These lines are slightly oblique and slope anteriorly from 

 the top of the whorl. The Pleistocene shells often retain their coloration of zigzag, 

 irregular, transverse, purple lines. 



This species is common in the upper San Pedro series of San Pedro; and in 

 tlie lower San Pedro series at San Pedro and Deadman Island. Found also in the 

 Pleistocene at Twenty-sixth Street, San Diego. 



Living. — San Pedro to Mazatlau (Cooper). 



Pleistocene. — San Pedro; San Diego (Cooper; Arnold). 



Family LXXXIII. TURBINID^. 



Genus Pachypoma Gray. 



Shell trochiform, conical, with moderately elevated spire; base concave, not umbilicated; 

 whorls flattened, rugose, spinously fringed. Operculum oval, subquadrangular, externally convex. 



Pachypoma cmlata Chem. is a characteristic species. 

 366. Pachypoma inaequale Marty n. 



Trochus incEqualis Mart., Univ. Conch., Lond., 17S4. 



Pachypoma inaqiiale Mart., Dall, Proc. U. S. Nat. Mus., Vol. XV, 1S92, p. 199, PL XXIII, 



figs. I, 3. 5- 

 Trochus gibberosus Chem., Conch. Cab., X, p. 278, vign. 23, 1795. 

 Pachypotna gibberosum Chem., Cpr., Brit. Assn. Rept., 1863, p. 651. Gabb, Pal. Cal., Vol. II, 



p. 83, 1869. Cooper, 7th Ann. Rept. Cal. St. Min., 1888, p. 256. Keep, West Coast 



Shells, p. 87, 1892. 

 Asiralium incequale Mart., Tryon, Man. Conch., Vol. X, p. 244, PL LVIl, figs. 51, 52, 1888. 



May 4, 190J. 

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