PLATE XXX. 
Miocene Echinoidea and Pelecypoda and Gasteropoda. 
(All figures natural size.) 
Fig.1. Verms (Chione) temblorensis Anderson. U.S.N.M. 164989. Exterior of imper¬ 
fect right valve; longitude 80 mm. Lower Miocene, head of Topanga 
Canyon, 3 miles south of Calabasas, Los Angeles County. Usually abun¬ 
dant in the lower Miocene; a nearly related, possibly identical form found 
in the upper Miocene. 
Fig. la. Top view of same specimen as fig. 1. 
Fig. 2. Mytilus matheivsonii Gabb var. expansus Arnold. U.S.N.M. 164968. Type. 
Right valve; altitude 10.5 mm. Lower Miocene, supposed equivalent of 
the Vaqueros formation, near Torrey Canyon wells, southwest of Piru, 
Ventura County. This species is usually found in the faunas of the lower 
Miocene through central and southern California. 
Fig. 3. Scutella fairbanksi Merriam. U.S.N.M. 164963. Same locality as fig. 2, but 
possibly at a somewhat lower horizon. 
Fig. 4. Ocinebra topangensis Arnold. U.S.N.M. 164995. Type. Back view; alti¬ 
tude 59 mm. Lower Miocene, Topanga Canyon, 3 miles south of Cala¬ 
basas, Los Angeles County. So far known only from this horizon. 
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