APPENDIX. 
320 
distant short longitudinal undulations on the body whorl; volutions of the spire rounded; 
longitudinally undulated. 
Locality. —Ocoya creek. 
SYCTOPUS. 
57. s. ocoyanus, Conrad, PI. VII, fig. 72 and 72a.—Spire depressed ; whorls flattened above ; 
shoulder sub-angulated, sides somewhat flattened, columella profoundly rounded above and 
concave below. 
Locality. —Ocoya creek. 
TURRITELLA. 
58. t. ocoyana, Conrad, PI. VIII, figs. 73, 73a, 736.—Volutions 13 or 14, straight at the 
sides ; rounded at base, and having well marked revolving lines, base broad ; volutions suddenly 
tapering to the apex. 
Locality. —Ocoya creek. 
COLUS. 
59. c. arctatus, Conrad, PL VIII, fig. 76.—Narrow, fusiform, whorls rounded ; beak very 
slender, somewhat sinuous. 
Locality. — Ocoya creek, Cal. 
TELL1NA. 
60. T. ocoyana, Conrad, PI. VIII, fig. 75 and 75 a. —Elliptical, compressed, inequilateral; 
posterior extremity acutely rounded, much above the line of the base ; anterior end somewhat 
acutely rounded ; cardinal teeth robust. 
PECTEN. 
61. p. nevadanus, Conrad, PI. VIII, fig 77.—Ovate, flat or slightly concave ; ribs 17? large, 
flattened on the back ; interstices strongly wrinkled transversely. 
This shell is so much nearly allied to N. Humphreysii of Maryland, that, taken in connexion 
with P. catilliformis, PL IS, it may be regarded as a Miocene species. The strata in which 
they occur may safely be referred to that period. 
Locality. —Ocoya creek. 
62. p. catilliformis, Conrad, Pl. IX, fig. 83.—Orbicular, plano-convex, with radiating striae 
and distinct rounded ribs ; ears equal. 
Locality. —Ocoya creek, 
This large Pecten has such a general resemblance to P. Madisonius, Say, of the Virginia 
Miocene, that I have no doubt it existed at the same period, or at least after the Eocene. There 
is none such now living on the coast of California, and none in the Eocene, of this group of 
large Pectens, which occur almost everywhere in the Miocene deposits of the Atlantic slope. 
In addition to the above described species, there are many specimens and drawings in which 
the specific characters are not preserved with sufficient distinctness for description. Among 
these are individuals of the genera Area, Solen, Dosinia and Venusw 
42 F 
