Acknowledgments ~ Field work and reconnaissance studies of

Acknowledgments ~
Field work and reconnaissance studies of existing
collections were carried out from 1983 * 1989, in the early
years as part of a cooperative project between the U.S.
Geological Survey and the Consejo de Recursos Minerales
of Mexico. Geologists who shared field support and
collected fossils included Cecelia McCloy, Matt Sabisky,
Susan M. Kidwell, Peter Sadler, Eric Gyllenhaal, James
Ashby, Hugh McLean, Gordon Gastii, M.E. Cassidy, J.R.
Neuhaus, M. Sawlan, and James G. Smith. Museum
collections were made available by Edward Wilson, Louella
Saul, and George Kennedy of the Los Angeles County
Museum; Paul Scott, Santa Barbara Museum of Natural
History; Michael Kellogg, .California Academy of Sciences;
Marilyn Kooser, University of California Riverside; W.K.
Emerson, American Museum of Natural History; and Luis R.
Segura V., Universidad Aut6noma de Baja California Sur.
Data from theses were provided by Cecelia McCloy, Raul
Rodriguez Q., Charles Powell, and Charles D. Winkler.
Access to critical localities in the Cabo Trough was
facilitated by Sr. Felipe Moreno A. of Rancho el Refugio, Sr.
Adan Fiol G. of Rancho la Trinidad, and Sr. Juan Angel •
Alvarez C. of Rancho Algodones. Transportation to
Cerralvo Island was arranged through the courtesy of Mr.
Ed. Burr, Pleasanton, California, and to Tiburon Island by
Mr. Eldon Heaston, Bah fa Kino, Sonora. Discussions with
J. Wyatt Durham, University of California Berkeley, of faunal
problems and the history of the Gulf of California and with
Susan M. Kidwell and Cecelia McCloy contributed new
insights to this ongoing research. Photographs are from
many sources: Kenji Sakomoto, Charles Powell, Ellen J.
Moore, and J.J. Smith. The manuscript was read by James
G. Smith. The help and encouragement of all is ,"
appreciated.
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_
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': 3"
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Pl.23. • ....•
Plate 4 Index spedes from the Gulf of California
Figure 1 Euvola keepi (Arnold, 1906) [ » E refugioensis->
(Hertlein, 1925)]. Holotype LSJU/CAS 5, ht. 7.5
cm, Ith. 7.4 cm. Imperial Formation, Latrania
Member, Coyote Mountains, CA.
Figures 2,3 Turritella imperials Hanna, 1926. Fig. 2,
hypotype USNM 418206, ht. 3.8 cm. Late
Miocene or early Pliocene, west of San Felipe,
Baja California, USGS loc. M9040 * CAS 40666.
Fig. 3, hypotype USNM 418205, ht. 5 cm.
Miocene, Imperial Formation, Latrania Sand
Member, Univ. California Berkeley loc. 738.
Figure 4 Spondylus ursipes Berry, 1959. RV, ht. cm, Ith '
cm. Holocene, Bahia de Adair, Sonora, Mexico.
Santa Barbara Museum of Natural History
spedmen.
Figure 5 Spondylus sp.cf. S. ursipes Berry, 1959 [ « S.
victoriae of Durham, 1950]. CAS voucher
spedmen 61210, ht. 15 cm, Ith. t2.3 cm. Late
Miocene or early Pliocene, west side of Sierra
San Felipe, Baja Caliornia, R.L Anderson the!
area, San Diego State University locality B6G-29.
Figure 6 Spondylus sp. aff. S. ursipes Berry, 1959 [ » S.
bostrychites Guppy of Hanna, 1926]. Ht. 11 cm,
Ith. 8 cm. Miocene, Imperial Formation,
southeastern Coyote Mountains, CA., Smith loc.
88JS9 » Kidwell loc. 88GSD-119. Also occurs at
southwestern Tiburon island and in the Boleo '
Formation near Santa Rosalia, B.C.S.