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PALAEONTOLOGY OP THE SURVEY. 
Height If inch, length If inch. A cast with a thin chalky coating of the shell, without a 
trace of external lines. 4 
Dosinia Montana, Pl. 6, fig. 4.—Suboval, inequilateral; length greater than height; con¬ 
vex ; anterior margin regularly and obtusely rounded ; posterior margin and base regularly 
rounded ; disk concentrically sulcated ; beaks. 
Locality. —Occurs with the preceding. 
Dosinia subobliqua, PI. 6, fig. 5.— Obtusely subovate, slightly oblique, convex; height 
exceeding the length ; concentrically sulcated. 
Locality. —Occurs with the preceding. 
With these species of Dosinia occur a small Venus, a Natica, and Pecten, in limestone. 
MYTILUS, Lin. 
Mytilus Inezensis, PI. 8, figs. 2 and 3.—Subovate-oblong ? ventricose anteriorly; compressed 
posteriorly; ribs radiating, numerous, bifurcated, and trifurcated near the inferior margins. 
Localities. —Santa Inez mountains and Santa Inez river. 
A few fragments of this species present the character of the ribs well defined, but the outline 
of the shell is uncertain. 
LUTRARIA, Lam. 
Lutraria transmontana, PI. 5, fig. 6.— Longitudinally ovate-triangular, inequilateral, 
thin; anterior end and base regularly rounded; posterior side cuneiform, extremity rounded; 
summits prominent; surface concentrically indented or subplicated, umbonal region concen¬ 
trically plicated; plicae irregular. 
Locality. —Ranch Triumpho, Los Angeles. 
This shell is allied to L. papyria, Con., and is well preserved in a hard, dark-colored lime¬ 
stone. There is another specimen from the shore between San Luis and Santa Barbara. 
AXINEA, Sow. PECTUNCULUS, Lam. 
Axinea Barbarensis, PI. 6, fig. 3.—Subglobose; equilateral; ribs about 35, little prominent, 
convex-depressed, interstices narrow, square. 
Locality. —Occurs with the preceding. 
Height 1^ inch. 
MACTRA ? 
Mactra? G-abiotensis, PI. 7, fig. 4.—Triangular, equilateral; anterior extremity acutely 
rounded, posterior extremity subangulated ; umbonal slope carinated, slightly curved. 
Locality. —Gaviote pass. 
A cast about one inch long, associated with a species of Mytilus and Infundibulum Gabiotensis. 
It may belong to the genus Schizodesma, Gray. 
GLYCIMERIS, Lam. PANOPAEA, Menand. 
Glycimeris Estrellanus, PI. 7, fig. 5.—Oblong or inclined to be trapezoidal, ventricose, 
very inequilateral, irregularly plicated concentrically, plicae more approximate and profound on 
the umbo, valves profoundly gaping posteriorly, margin obliquely truncated ; ligament margin 
incurved, elevated posteriorly. 
Locality. —Panza and Estrella valleys. 
A cast, allied to Panopaea refiexa , Say; length 3 inches. 
