358 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. XXXYV. 
ECANSIMBIRORODA. . 
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TURRITELLA PESCADEROENSIS, new species. 
JMB DOROKTL, ae, |Z 
1895. Turritella hoffmani ASHLEY (not GABB), Neocene Santa Cruz Mts., 
Proce. Calif. Acad. Sei., Ser. 2, V, 1895, p. 299: 
Description.—Shell elongate, conical, large, often attaining a diam- 
eter of over 25 mm.; apex acute. Whorls at least 10, flat to convex 
above, convex below, excavated at base; there are 4 prominent, sub- 
equal, strong, squarish, often more or less nodose revolving ribs sep- 
arated by concave-bottomed, channeled interspaces equal to or nar- 
rower than the ribs; the 2 lower ribs are usually slightly larger 
than the 2 upper; in addition to the 4 major ribs there are 2 sutural 
ribs, less prominent and more rounded than the others, one on each 
side of the suture and close to it, and sometimes an intercalated re- 
volving raised line in one or more of the interspaces; fine incremental 
lines are visible in some specimens; base spirally striate; aperture 
subquadrate. 
Dimensions.—Lenegth (restored), about 110 mm.; latitude, 25 mm.; 
apical angle, 14°. | 
Notes—A comparison of this robust species with some specimens of 
T. chicoensis Gabb from Pentz, Butte County, near the type-locality 
of the latter, reveals the following differences: 7’. pescaderoensis is 
larger, relatively broader (7. chicoensis has a deflection of 11° to 
12°), has a much less pronounced basal excavation, has much stronger 
and more nearly equal and closer spaced revolving ribs, which are 
usually more rugose, and has more prominent sutural riblets. Speci- 
mens, which are believed to be a variety of 7. chicoensis, from the 
Chico formation of the Santa Ana Mountains, Orange County, more 
closely resemble 7. pescaderoensis than the typical form, being almost 
equal to the former in size and relative width, but showing the sculp- 
ture characteristics of the typical 7. chicoensis. Named for the town 
of Pescadero, near which is the type-locality. 
Type.—Imperfect specimen showing 3 large whorls, L. S. J. U., No. 
YQ, (locally IN@, BF A.) 
Horizon.—Chico formation, upper Cretaceous. 
Localities —Santa Cruz quadrangle, San Mateo County, locality 
No. 27 A, about 21 miles north of Bolsa Point, in transition sandstone 
and conglomerate layers between the thin-bedded sandstones below 
and the heavy-bedded coarse conglomerate above. (G. H. Ashley, 
J. M. Hyde, J. F. Newsom, R. Arnold.) 
