9. 
EXPLANATION OF PLATH XXXV. 
MONTEREY (MIDDLE MIOCENE) AND UPPER MIOCENE FOSSILS. 
. Arca obispoana Conrad, Cat. No. 165462, U.S.N.M. Casts of right and 
left valves; length of more nearly perfect specimen, 42 mm. X 1. 
Monterey formation, middle Miocene, locality No. 125, at confluence 
of Zayante and Bean creeks. Usually quite abundant in the Mon- 
terey formation. 
. Mactra montereyana, new species, type, Cat. No. 165468, U.S.N.M._ 
Exterior of both valves; altitude of each, 831 mm. X 1. Monterey 
formation, middle Miocene, locality No. 122, Love Creek, 1 mile above 
its confluence with the San Lorenzo River, p. 381. 
. Yoldia impressa Conrad, Cat. No. 165465, U.S.N.M. Cast of distorted 
(longitudinally elongated) right valve showing teeth of left valve; 
length, 26 mm. X 1.. Monterey formation, middle Miocene, locality 
No. 121, Newell Creek, 14 miles above its confluence with the San 
Lorenzo River. Abundant in the Monterey; also found in the 
Oligocene. 
. Venericardia montereyana, new species, type, Cat. No. 165464, U.S.N.M. 
Left valve of slightly distorted specimen; length, 10 mm. X 2. Mon- 
terey formation, middle Miocene, locality No. 121, same as fig. 3, p. 380. 
. Agasoma stanfordensis, new species, type, L.S.J.U., No. 1087. Back view 
of cast of imperfect specimen ; altitude, 52 mm. X 1. Upper Miocene, 
locality No. 4, Tusk Gully, 24 miles south of Mayfield, p. 384. 
. Leda taphria Dall, L.8.J.U., No. 1069. Right valve; length, 18 mm. X 2. 
Upper Miocene, locality No. 42, west face of hill on east side of Ma- 
dera Creek, 24 miles south-southwest of Mayfield. Also found in the 
Pliocene and Quaternary faunas. 
. Fusus stanfordensis, new species, type, L.S.J.U., No. 1081. Back view 
of sandstone cast of nearly perfect specimen; altitude, 49 mm. X 1. 
Upper Miocene, locality No. 42, same as fig. 6, p. 383. 
. Periploma sanctecrucis, new species, type, L.S.J.U. No. 1074. Partially 
decorticated right valve; length, 43 mm. X 1. Upper Miocene, lo- 
cality No. 42, same as fig. 6, p. 382. 
Yoldia supramontereyensis, new species, type, L.S.J.U., No. 1067. Im- 
perfect left valve; length, 40 mm. X 1. Upper Miocene, locality No. 
4, same as fig. 5, p. 382. 
10. Astrodapsis antiselli Conrad, Cat. No. 165466, U.S.N.M. Top view; 
length, 54 mm. X 1. Santa Margarita formation, upper Miocene, 
U. S. Geological Survey locality No. 4144, 2 miles south of San 
Lucas, Monterey County. 
