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JOURNAL OF PALEONTOLOGY, V. 60, NO. 4, p. 851-864, 3 FIGS., JULY 1986

NEW EARLY MOLLUSKS FROM THE OROCOPIA MOUNTAINS, SOUTHERN CALIFORNIA

RICHARD L. SQUIRES AND DAVID M. ADVOCATE Department of Geological Sciences, California State University, Northridge 91330 and Exxon Company USA, Thousand Oaks, California 91359-5025

ABSTRACT—Five new species of mollusks are described from the early Eocene Maniobra Formation, northeastern Orocopia Mountains, southern California. The new species are from the basal part of the formation, and the fauna is indicative of the West Coast provincial molluscan early Eocene "Capay Stage." The mollusks are shallow-marine forms that were transported a short distance into slope/upper submarine-canyon deposits. Chedevillia saltonensis n. sp. and Eocypraeal maniobraensis n. sp. resemble Eocene species from Paris Basin, France. () louella n. sp. is the earliest North American species of Semicassis. Volutilithes orocopiaensis n. sp. is the earliest North American species of this and resembles V. muricinus from Paris Basin. (Meiocardia) susukii n. sp. is the earliest reported species of Meiocardia on the West Coast of North and South America. gallica, a species previously only known from lower Eocene strata in the Anglo-Paris Basin, is tentatively identified from the Maniobra Formation. Campanilopa dilloni, previously only known from south-central California, is present in the formation. Supplementary descriptions and illustrations are given for these two species. The Maniobra species described have a close relationship to species characteristic of the Eurasian Tethyan paleobiogeographic province. The age of the Maniobra mollusks permits greater resolution of the timing of the westward migration of the Eurasian species, indicating that much of it occurred during early Eocene and/or late time.

INTRODUCTION vertebrate provincial "Capay Stage" of early THE new mollusks reported in this study were Eocene age. Their assignment was based on collected from the early Eocene Maniobra the presence of Clavilithes cf. C. tabulatus, Formation, northeastern Orocopia Moun- Galeodea cf. G. sutterensis, Chedevillia cf. C. tains, Riverside County, California (Figure stewarti, and on benthic foraminifers. Clavi- 1). This formation was discovered in 1955 lithes tabulatus recently has been shown by (Crowell and Susuki, 1959) and dated as being Squires (1983, 1984) to occur in both the of early and middle Eocene age. This dating "Capay Stage" (restricted sense of Givens, can now be refined and the Maniobra is early 1974) and the overlying "Domengine Stage." early Eocene through late early Eocene in age. Galeodea cf. G. sutterensis and Chedevillia cf. It is the only known marine Eocene exposure C. stewarti are reidentified in this present pa- south of the Tehachapi Mountains and east per as Galeodea cf. gallica and Chedevillia of the San Andreas fault in southern Cali- saltonensis n. sp., respectively. A "Capay" fornia. age for CSUN locality 662, nevertheless, is The Maniobra Formation has a maximum still maintained. It is based, in part, on the thickness of 1,460 m and consists of silici- presence of the bivalve Odontogryphaea? clastics that locally contain some macro- haleyi, which is confined to the "Capay Stage" fossils and microfossils. These deposits rep- (Givens, 1974). Foraminifera indicative of resent a transitional marginal marine to P7 to P9 Zones and calcareous nannofossils deep-water submarine-fan sequence depos- indicative of CP9 to CP11 Zones also have ited in subtropical waters (Advocate, 1983). been found 58 m upsection from CSUN lo- Most of the new mollusks are from Cali- cality 662 (Advocate, 1983). These zones are fornia State University, Northridge (CSUN) of earliest Eocene through late early Eocene locality 662 (Figure 1), which is 57 m above age (Berggren et al., in press) and correspond the base of the formation. This locality is the mostly to the restricted "Capay Stage" (Saul, same as University of California, Los Angeles 1983). In addition, about 740 m upsection locality 3779, which Crowell and Susuki from CSUN locality 662, there is an occur- (1959) assigned to the West Coast macroin- rence of Turritella meganosensis protumes- Copyright © 1986, The Paleontological Society 851 0022-3360/86/0060-0851 $03.00 852 RICHARD L. SQUIRES AND DA VID M. ADVOCATE

environment because of the presence of bathyal foraminifers (Advocate, 1983). The shallow-marine macrofossils retain delicate ribbing and must have been trans- ported in a medium in which abrasion was minimal. Odontogryphaeal haleyi specimens are common, but all are disarticulated left valves. Small specimens of Glyptoactis mcmasteri are mostly articulated, as are fairly common small specimens of the brachiopods Eogryphus cf. E. tolmani ynezensis and Kin- gena simiensis. Locality 662 contains the most diverse fau- na of any locality in the Maniobra Forma- tion. Macrofauna present, including four new species of mollusks, comprises 21 gastro- pods, six bivalves, two brachiopods, and one species each of scaphopod, calcareous an- FIGURE 1— Index map to California State Uni- nelid tube, discocyclinid, and spatangoid. In versity, Northridge (CSUN) collecting localities, addition, there are terrestrial plant fragments. Maniobra Formation, northeastern Orocopia A new species of cassid gastropod is from Mountains, southern California. CSUN locality 665, a lateral equivalent of the fossil-bearing bed at CSUN locality 662. cens at CSUN locality 671. This taxon is con- A specimen of Velates perversus, a gastropod fined to the "Capay Stage" and is especially that is indicative of the Eurasian Tethyan diagnostic of the uppermost "Capay Stage" paleobiogeographic province (Vokes, 1935; (Saul, 1983; Squires, 1984). Clark and Vokes, 1936; Palmer, 1967), was Upsection from CSUN locality 671, the also found at this locality. Maniobra Formation contains species that At locality 668, about 200 m above the have been reported (Givens, 1974; Givens base of the formation and within the "Capay and Kennedy, 1979; Saul, 1983; Kappeler et Stage" portion of the Maniobra, are sparse al., 1984; Squires, 1984) elsewhere on the macrofossils in sandy conglomerate beds in- West Coast as confined to the "Domengine terpreted to have formed in the upper part Stage"; namely, Lyriscapha lajollaensis, Tur- (landward) of a submarine-canyon channel ritella uvasana applinae, Turritella andersoni complex (Advocate, 1983). A large, incom- lawsoni, Lyria andersoni, and Venericardia plete specimen of the cerithiid gastropod (Pacificor) hornii calafia. Based on calcareous Campanilopa dilloni Hanna and Hertlein oc- nannofossils and mollusks in the Llajas For- curred as a conglomerate clast and had ob- mation, Simi Valley, southern California, Saul viously undergone postmortem transport al- (1983) and Squires (1984) reported the "Do- though the amount of abrasion was not great. mengine Stage" to be of late early through The species described in this report, as well early middle Eocene age. With the exception as the Maniobra specimen of Velates perver- of T. u. applinae, all the above-listed taxa sus, help to further document Clark and which are indicative of the "Domengine Vokes' (1936) conclusion that an important Stage" in the Maniobra Formation are con- trans-Atlantic migration route existed be- fined to the early Eocene portion of the "Do- tween western Europe and western North mengine Stage" of the Llajas Formation; America during the Eocene. According to namely, the shallow-marine (transgressive) Zinsmeister (1983), the first indication of this facies (Squires, 1984). Based on this, it is con- influx of large numbers of mollusks was in cluded that the upper portion of the Manio- the late Paleocene and continued into the ear- bra Formation is of late early Eocene age. ly Eocene. Squires (1984) showed that this At CSUN locality 662, the macrofossils are influx of mollusks into western North Amer- in a few discontinuous, thin sandy mudstone ica continued into early middle Eocene time. beds interpreted to have formed in a slope Letter abbreviations used for catalog and NEW EOCENE MOLLUSKS FROM CALIFORNIA 853 locality numbers are: CAS = California of western Iran, except that C. dilloni has Academy of Sciences; CSUN = California fewer nodes and a much more projecting ca- State University, Northridge; LACMIP = Los rina. Campanile mprgani is more strongly Angeles County Museum, Invertebrate Pa- sculptured than Campanile symbolicum Ire- leontology Section; UCLA = University of dale, the type species of Campanile {fide Ire- California, Los Angeles; and UCMP = Uni- dale, 1917), and may belong to Campanilopa. versity of California Museum of Paleontol- Douville (1904) reported his new species C. ogy (Berkeley). morgani to be from Maastrichtian strata. Da- vies (1975, p. 84), however, referred these SYSTEMATIC PALEONTOLOGY strata to the Danian, but considered the Dan- ian to be . More stratigraphic work Phylum Cuvier, 1797 is needed. Class Cuvier, 1797 Discussion.— As noted by Wrigley (1940) Subclass PROSOBRANCHIA Milne Edwards, 1848 and discussed by Iredale (1917) and Hanna and Hertlein (1949), there has been consid- Order MESOGASTROPODA Thiele, 1925 erable confusion regarding whether or not Superfamily CERITHIACEA Fleming, 1822 Cerithium giganteum Lamarck, 1804, should be the type species of Campanile. According Family Fleming, 1828 to Iredale (1917), Campanile already had a Genus CAMPANILOPA Iredale, 1917 type species; namely, Cerithium laeve Quoy Type species.-By original designation, Cer- and Gaimard, 1834. Because C. laeve is a ithium giganteum Lamarck, 1804, middle junior homonym, Iredale (1917) replaced C. Eocene (Lutetian Stage), Paris Basin, France. laeve Quoy and Gaimard with Campanile symbolicum Iredale, 1917, and provided the CAMPANILOPA DILLONI supraspecific taxon Campanilopa for the sep- Hanna and Hertlein, 1949 arate and distinct group of Cerithium gigan- Figure 2.1 teum Lamarck. Douville (1904) compared his Campanilopa dilloni HANNA AND HERTLEIN, 1949, new species Campanile morgani to Ceri- p. 392-394, PI. 77, figs. 1-4; GIVENS, 1974, p. thium laeve = Campanile symbolicum and 69, PI. 7, fig. 10. did not mention Cerithium giganteum, al- Supplementary description. — Turreted- though all of his forms have well developed elongate shell of very large size; . and upper missing; whorls slightly con- Campanilopa, as a subgenus of Campanile, cave, becoming flat sided in later whorls; pos- has been reported with certainty from strata terior portion of each whorl with a very pro- of early Paleocene (Danian) through late jecting, greatly thickened carina with eight to Eocene age in Europe (Delpey, 1941). ten pointed nodes, sides of whorls with three Campanilopa dilloni is the earliest species to four swollen spiral cords; groove along in- of this genus on the West Coast of the United side of carina in later whorls; outer miss- States. Its molluscan stage range is from the ing and obscured by matrix. "Capay" through probably lower "Domen- Comparison.— As mentioned by Hanna gine" (Hanna and Hertlein, 1949; Givens, and Hertlein (1949), Campanilopa dilloni 1974). Its geographic distribution is now from closely resembles Campanile incomptum the Orocopia Mountains through south-cen- Dixon (1850, p. 101, PI. 6, fig. 18; Cossmann tral California. and Pissarro, 1910-1913, PL 25, fig. 137-46; A supplementary description of C. dilloni not Deshayes, 1866, p. 116, Pl. 77, fig. 1 = is given for two reasons. Firstly, the anterior Campanile giganteum (Lamarck) fide Del- half of the Maniobra specimen represents pey, 1941, p. 15) from the Lutetian Stage, older growth-stage material than the speci- Paris Basin, France, except that in C. dilloni mens used by Hanna and Hertlein (1949) in the nodes are confined to the much more their original description of the species. Sec- projected carina. ondly, although they figured an early stage of Campanilopa dilloni also resembles Cam- growth (holotype, CAS 9425; Pl. 77, fig. 4) panile morgani Douville (1904, p. 312-313, and a middle stage of growth (paratype, CAS Pl. 43, figs. 1-11) from early Paleocene? strata 9428; Pl. 77, fig. 2), they only described the 854 RICHARD L. SQUIRES AND DA VID M. ADVOCATE NEW EOCENE MOLLUSKS FROM CALIFORNIA 855 early stage of growth. The posterior half of least seven rounded whorls; sculpture not the Maniobra specimen corresponds in preserved in posteriormost spire whorls; growth stage and in morphologic detail to preantepenultimate whorl covered only by paratype, CAS 9428. The morphology of the closely spaced spiral ribs; other spire whorls Maniobra specimen does not change signif- and covered by numerous evenly icantly from posterior to anterior portions. spaced and equal-weight, collabral and pri- The specimen does not have, however, the mary spiral ribs that produce an intricate can- flat-sided appearance, the 14 to 16 carina cellate pattern; angulate shoulder on aper- nodes, or the six spiral ribs that the early tural half of body whorl with small nodes on growth-stage holotype, CAS 9425, possesses. collabral ribs; impressed with a fairly Material. — Later whorls of a large, incom- strong sutural cord on lower spire whorls and plete adult specimen. body whorl; outer lip missing; inner lip cov- Repository. — Hypotype, LACMIP 7165. ered by that passes into an irregular Occurrence. — Hypotype, LACMIP 7165 solid flange that extends from was obtained from the early Eocene "Capay region to shell along right margin of Stage" portion of the Maniobra Formation shell; anterior canal missing. from a coarse sandstone approximately 200 Comparison. — Chedevillia saltonensis n. sp. m above the base of the formation, at CSUN resembles the California species, C. stewarti, locality 668. as well as the Paris Basin species C. mirabilis and C. munieri. It differs from C. stewarti Superfamily STROMBACEA Clark (1942, p. 116-117, Pl. 19, figs. 7-11), Rafinesque, 1815 a species from upper Paleocene strata in the Simi Valley area, southern California (Squires, Family STROMBIDAE Rafinesque, 1815 1984), in the following features: finer and Genus CHEDEVILLIA Cossmann, 1906a more numerous collabral costae, coarser pri- Type species. — By original designation, Ri- mary spiral ribs, nodes on body whorl shoul- mella munieri Chedeville, 1904a, middle der only on apertural half of whorl and not Eocene (Lutetian Stage), Paris Basin, France. elongate, and collabral costae do not notice- Diagnosis. — Inflated-fusiform shell of me- ably decrease in number per whorl in the later dium size; whorls convex, with narrow col- stages of growth. In addition, in the inter- labral costae and spiral ribs; aperture narrow, spaces between the primary spiral ribs of C. outer lip thin, bent, drawn out into a solid saltonensis, there are two or three very fine flange (rostrum) that extends to shell apex, spiral threads, whereas in C. stewarti there no posterior canal or notch on flange; inner are none. The evenly spaced, equal-weight lip smooth and calloused, callus merges with collabral and primary spiral ornamentation flange. in C. saltonensis produces an intricate can- cellate pattern, but in C. stewarti no such con- CHEDEVILLIA SALTONENSIS n. sp. Figure 2.2-2.4 dition is present. It also is not present in C. mirabilis (Deshayes, 1866, p. 457, Pl. 89, figs. Chedevillia sp. cf. C. stewarti Clark. CROWELL AND 7-9; Chedeville, 1904b, p. 380; Cossmann, SUSUKI, 1959, PL. 2, figs. 2, 3. 1904, Pl. 3, fig. 20; Cossmann and Pissarro, Diagnosis.—A Chedevillia with an intri- 1910-1913, Pl. 31, fig. 157-15), a species from cate cancellate sculpture pattern. Ypresian and Cuisian strata of the Paris Ba- Description. -Inflated-fusiform shell of sin. These strata are late early Eocene in age medium size; spire about 50% of height and and in the upper Ypresian Stage = Cuisian curved toward back of shell; teleoconch of at Substage (Pomerol, 1982). Chedevillia sal-

FIGURE 2—1, Campanilopa dilloni Hanna and Hertlein, hypotype, LACMIP 7165, CSUN loc. 668, x0.5. 2-4, Chedevillia saltonensis n. sp., holotype, UCLA 28987, CSUN loc. 662, x2. 2, apertural view; 3, side view; 4, abapertural view. 5, 6, Eocypraeal maniobraensis n. sp., holotype, UCLA 48431, CSUN loc. 662, x 1.25. 7, 8, Galeodea cf. G. gallica Wrigley, hypotype, UCLA 28988, CSUN loc. 662, x 1.7. 9, 10, Galeodea gallica Wrigley, hypotype, UCMP B-5415, Parisis Fontaine, Paris Basin, France, xl.9. 11, 12, Phalium (Semicassis) louella n. sp., holotype, LACMIP 7166, CSUN loc. 665, x 1.7. 856 RICHARD L. SQUIRES AND DA VID M. ADVOCATE

tonensis, furthermore, differs from C. mira- Eocene (Lutetian-Bartonian Stages), Paris bilis in having finer collabral costae and Basin, France. coarser primary spiral ribs. Diagnosis. — Inflated-pyriform shell of Chedevillia saltonensis differs from C. mu- small to medium size; spire involute; body nieri (Chedeville, 1904a, p. 101-102, fig. 1 whorl smooth with long, very narrow aper- (two views); 1904b, p. 380; Cossmann, 1906a, ture elongated anteriorly, curved posteriorly; PI. 14, fig. 8; 1906b, PI. 5, fig. 157-14, PI. 6, inner lip with numerous weak teeth, terminal fig. 157-14; Cossmann and Pissarro, 1910— columellar tooth of one or two ridges; outer 1913, PI. 31, fig. 157-14; Wenz, 1940, fig. lip moderately flat with uniformly spaced nu- 2735; Clark, 1942, PI. 19, figs. 13, 14), a merous teeth; fossula broad, its inner edge species from middle Eocene strata (Lutetian smooth with no columellar furrow. Stage) of Paris Basin, in the following fea- tures: finer collabral costae; presence of col- labral costae on the antepenultimate whorl; EOCYPRAEA? MANIOBRAENSIS n. sp. and, no bifurcation of the collabral costae on Figure 2.5, 2.6 the body whorl. Diagnosis.— An Eocypraea-like, very in- Discussion. — Crowell and Susuki's (1959, flated shell. PI. 2, figs. 2, 3) figured specimen is the same Description. — Very inflated, ovate-pyri- one (holotype, UCLA 28987) figured in this form shell of medium size; maximum di- report. ameter in middle of shell; spire involute; nar- Cossmann (1906a) and Wenz (1940) re- row aperture near right margin of shell, ported Chedevillia only from the Eocene in elongate anteriorly and curved posteriorly; Europe. Clark (1942) recognized this genus extreme anterior end missing; inner lip with in North America, and named Chedvillia numerous small teeth; thickened outer lip steward but misspelled the generic name. He narrow, with numerous teeth that become placed the type locality (UCMP locality 7015) stronger in the anterior direction. of this species in the Llajas Formation, Simi Comparison.— The new species is most Valley, southern California; but, as discussed similar to Eocypraea inflata (Lamarck, 1802, in Squires (1984), this locality actually plots p. 389; 1805, PI. 2, fig. la, lb) from the mid- within the lower part of the Santa Susana dle Eocene (Lutetian-Bartonian Stages) of Formation and is of late Paleocene age. Paris Basin, France. Other workers who have Material. — One nearly complete adult described and/or illustrated the type species specimen and the upper spire of an adult of Eocypraea include Deshayes (1824, p. 724, specimen. PI. 97, figs. 7, 8), Cossmann (1903, p. 162- Repository. —Holotype, UCLA 28987; 163, PI. 9, figs. 18, 19), Cossmann and Pis- paratype, UCLA 59725. sarro (1910-1913, PI. 32, fig. 162-7), Wenz Occurrence. — Both specimens were ob- (1941, p. 1004, fig. 2882), and Palmer (1977, tained from the early Eocene "Capay Stage" PI. 2, fig. 6a, 6b). portion of the Maniobra Formation from a Eocypraea? maniobraensis differs from 30 cm thick bed approximately 57 m above UCLA collection specimen 32794 of E. in- the base of the formation, at CSUN locality flata from Chaumont en Vexin (Oise), France, 662 (which is equivalent to UCLA locality in the following features: a narrower and more 3779). elongate shell, a much more inflated apertural Etymology. — This species is named for the side of the body whorl, and a much narrower Salton Sea, which is immediately southwest outer lip. of the Orocopia Mountains. Discussion.— As a result of crushing, the interior of the aperture of the Maniobra spec- Superfamily CYPRAEACEA Gray, 1824 imen cannot be observed, and the nature of Family Fleming, 1828 the fossula cannot be determined. Positive Subfamily EOCYPRAEINAE generic assignment, therefore, cannot be Schilder, 1924 made. Genus EOCYPRAEA Cossmann, 1903 The classification of Eocypraea follows that Type species. — By original designation, ofSchilder(1966,1967). This genus is known Cypraea inflata Lamarck, 1802, middle from strata of Late Cretaceous (Cenomanian) NEW EOCENE MOLLUSKS FROM CALIFORNIA 857 through late Miocene age in Europe, West Etymology. — The species is named for the Africa, West Pakistan, Indonesia, North Maniobra Formation. America (Atlantic and Pacific Coasts), Ca- ribbean region, South America (Pacific Coast), Superfamily TONNACEA Suter, 1913 and possibly New Zealand (Schilder, 1932; Family Swainson, 1832 Wenz, 1941; Davies, 1971). Genus GALEODAE Link, 1807 Prior to Eocypraea? maniobraensis n. sp., workers (Schilder, 1932; Vokes, 1939; Zins- Type species.— By monotypy, Buccinum meister, 1974) had assigned four species from echinophorum Linne, 1758, Recent, Medi- the West Coast of the United States to Eocy- terranean. praea: Ovula martini Dickerson, 1914, O. GALEODEA cf. G. GALLICA Wrigley, 1934 novasumma Nelson, 1925, Cypraea? bayer- Figure 2.7, 2.8 quei Gabb, 1864, and Cypraea castacensis Stewart, 1927. None of these four species has Galeodea sp. cf. G. sutterensis Dickerson. CRO- the characteristics of Eocypraea. Ovula mar- WELL AND SUSUKI, 1959, p. 588, Pl. 2, figs. 1, 4 tini is from late Paleocene strata in central Supplementary description. — Subglobose California (Dickerson, 1914; Keen and Bent- shell of medium size with moderately ele- son, 1944). The flattened ventral surface and vated spire and large body whorl; protoconch very thick outer lip suggest that this species conical, multispiral, smooth; uppermost spire belongs in Cypraea. Ovula novasumma is whorls rounded with spiral lirae; antepenul- from late Paleocene strata in southern Cali- timate whorl convex with spiral lirae and faint fornia (Nelson, 1925; Keen and Bentson, collabral riblets, middle to lower portion of 1944). It has smooth inner and outer lips and whorl angulate due to presence of a strong does not belong in Eocypraea. Cypraea? bay- spiral rib; penultimate whorl flat-sided and erquei is from late Paleocene through late covered by spiral lirae, noded carina just Eocene strata in California (Gabb, 1864; Keen above suture; body whorl flat-sided to slight- and Bentson, 1944). Its flattened ventral sur- ly concave, covered by numerous fine, spiral face and broad outer lip suggest that this lirae; shoulder carina with 12 to 13 nodes, species belongs in Cypraea as indicated by two well developed carinae on middle por- Ingram (1942). Cypraea castacensis is found tion of body whorl less noded; middlemost in late early through early middle Eocene carina on body whorl closer to anteriormost strata (i.e., "Domengine Stage") in southern carina than to carina on shoulder. and central California (Squires, 1984). The Aperture oval, outer lip thickened and re- flattened ventral surface, broad outer lip, po- flected, inner lip with a smooth, thin parietal sition of the aperture just right of the mid- callus; anterior canal region missing. line of the shell, and deep notches at both Comparison. — The Maniobra specimens ends suggest that this species also belongs in of this gastropod are very much like speci- Cypraea. Ingram (1942), Stewart (1927), and mens of Galeodea gallica from Parisis Fon- Squires (1984) assigned this species to Cy- taine, Paris Basin, France. Comparison of the praea. preserved parts of the Maniobra specimens If Eocypraea? maniobraensis n. sp. does to an actual specimen (hypotype, UCMP belong in Eocypraea, it represents the earliest B-5415) (Figure 2.9, 2.10) and published de- typical species of Eocypraea on the West scriptions/illustrations of G. gallica (De- Coast of the United States. shayes, 1835, p. 633-634, Pl. 85, figs. 1, 2; Material. —One nearly complete adult 1866, p. 476, 477; Cossmann and Pissarro, specimen with shell material partly missing, 1910-1913, Pl. 34, fig. 166-2) from the Paris and slightly crushed. Basin revealed no significant morphologic dif- Repository. — Holotype, UCLA 48431. ferences. Occurrence.—Specimen was obtained from The Maniobra specimens are less like spec- the early Eocene "Capay Stage" portion of imens of G. gallica (Wrigley, 1934, p. 123— the Maniobra Formation from a 30 cm thick 125, Pl. 16, figs. 24, 25; British Museum Nat- bed approximately 57 m above the base of ural History, 1975, p. 11, Pl. 21, fig. 4) from the formation, at CSUN locality 662 (which the London, England, area. The English spec- is equivalent to UCLA locality 3779). imens, which show more variety than the typ- 858 RICHARD L. SQUIRES AND DA VID M. ADVOCATE cial forms from the Paris Basin, have up to it would be the first occurrence of this species 15 nodes on the shoulder of the body whorl, in the Western Hemisphere. a tendency toward collabral ribs, a possible Material. —Five nearly complete adult at 180° or 360° from the aperture, and specimens and eight partial adult specimens. a possible slightly developed fourth carina on Repository. -Hypotypes, UCLA 28988, the body whorl (Wrigley, 1934). 48435, 59726. The Maniobra specimens are incomplete Occurrence. —Specimens were obtained and badly pitted and corroded from weath- from the early Eocene "Capay Stage" portion ering. The nodes on the carinae, for example, of the Maniobra Formation from a 30 cm probably have been diminished in size due thick bed approximately 57 m above the base to the weathering, as have the spiral ribs. Such of the formation, at CSUN locality 662 (which preservation problems, therefore, do not al- is equivalent to UCLA locality 3779). low positive specific identification, and the Maniobra specimens are tentatively assigned Genus PHALIUM Link, 1807 to G. cf. G. gallica. Type species.— By subsequent designation The most characteristic feature of G. gal- (Dall, 1909), Buccinum glaucumlAnne, 1758, lica and G. cf. G. gallica is the presence of Recent, Indo-Pacific. three nodose carinae on the body whorl. Be- cause there are three carinae rather than two, Subgenus SEMICASSIS Morch, 1852 they differ from West Coast species of Ga- Type species.— By subsequent designation leodea, except for G. sutterensis Dickerson (G. F. Harris, 1897), japonica Reeve (1916, p. 492, PI. 40, figs. 1, 2) from early {=Phalium bisulcatum Schubert and Wagner, Eocene strata of California and southwestern 1829), Recent, Indo-Pacific. Oregon. See Vokes (1939) for a refined de- Diagnosis.— Ovate shell of medium size scription of G. sutterensis. with moderately low acuminate spire; pro- Galeodea gallica and G. cf. G. gallica differ toconch whorls conical, smooth; teleoconch from G. sutterensis in the following features: whorls convex, body whorl well-rounded, 12 to 15 nodes on the shoulder of the body usually only an outer lip varix; whorls sculp- whorl rather than 8 or 9, small nodes to tu- tured by numerous spiral threads; outer lip bercles rather than spinose tubercles, much thickened and finely denticulate, base of out- less angulated spire whorls, and slightly er lip lacks terminal spines; inner lip with coarser spiral threads that cover the shell. wrinkled columellar shield; short anterior ca- Discussion. — Crowell and Susuki's (1959, nal with a longitudinally threaded siphonal PI. 2, figs. 1, 4) figured specimen is the same fasciole. one (hypotype, UCLA 28988) figured in this report (Figure 2.7, 2.8). PHALIUM (SEMICASSIS) LOUELLA n. sp. For a synonymy of G. gallica, see Wrigley Figure 2.11, 2.12 (1934). Prior to his work, the preoccupied Diagnosis. — A Semicassis with three evenly name Galeodea diadema was used for the spaced carinae, no varices (other than a pos- Paris Basin specimens of G. gallica. sible one on outer lip), and covered by fine Previously, G. gallica has been reported spiral threads. only from the upper Cuise sands in the Paris Description.— Ovate-globular shell of me- Basin (Deshayes, 1835, 1866; Chedeville, dium size; spire about 20% of the height; pro- 1904b; Lhomme, 1904; Cossmann and Pis- toconch missing; teleoconch of at least four sarro, 1910-1913; Glibert, 1963) and the whorls; whorls angulate, covered by closely- Pyrenees (Wrigley, 1934), as well as from the spaced fine spiral threads; shoulder of pen- London Clay in southern England (Wrigley, ultimate whorl marked by a carina with nu- 1934). The Cuise sands are late early Eocene merous nodes; body whorl with three evenly in age and correspond to the upper Ypresian spaced carinae: carina along shoulder of body Stage = Cuisian Substage (Pomerol, 1982). whorl with about 16 spinose nodes, carina The London Clay is primarily early Eocene along middle portion of body whorl less no- in age (Curry et al., 1978). If G. gallica ac- dose, and anteriormost carina less pro- tually does occur in the Maniobra Formation, nounced and not nodose; outer lip mostly NEW EOCENE MOLLUSKS FROM CALIFORNIA 859 absent with faint suggestion of a varix; inner Etymology.— This species is named in lip with only a faint trace of a very thin pa- honor of LouElla R. Saul for her many im- rietal callus; anterior canal mostly absent with portant contributions to the study of Late a faint trace of a siphonal fasciole. Cretaceous and early Tertiary mollusks of the Comparison.— The new species is similar West Coast. in overall shape, size, and sculpturing to Phalium (Semicassis) tuberculiformis (Han- Order Wenz, 1938 na, 1924). A synonymy for this species is Superfamily VOLUTACEA Rafinesque, 1815 given in Squires (1984). The best descriptions Family Rafinesque, 1815 of P. 0S.) tuberculiformis are given in Schenck Subfamily VOLUTILITHINAE (1926, p. 83-84, Pl. 14, figs. 12-16) and in Pilsbry and Olsson, 1954 Vokes (1939, p. 149-150, Pl. 19, figs. 19,21, Genus VOLUTILITHES Swainson, 1829 23-27). Type species.— By subsequent designation Phalium (S.) louella differs from P. (S.) (Dall, 1906), Voluta muricina Lamarck, 1802, tuberculiformis in the following features: no middle Eocene (Lutetian Stage), Paris Basin, varix on the body whorl (other than on the France. lip), smaller nodes on the carinae, finer spiral Diagnosis. — Fusiform shell of medium to threads, and the spiral threads do not have a slightly large size, shouldered, with elevated fine cancellate-sculpture pattern caused by spire nearly equal to length of the aperture; growth lines intersecting with the spiral protoconch whorls smooth, cylindrical, with threads. apical end pointed; teleoconch whorls convex Discussion. — The basis of modern taxo- with sculpture of strong, collabral costae nomic work on Phalium, Semicassis, and which are spiniform or nodose on shoulder, closely related genera and subgenera are the surface otherwise smooth or marked with fine articles by Abbott (1968) and Kanno (1973). . Abbott (1968) included Semicassis as a sub- with prominent anterior fold and genus of Phalium, but he did so hesitantly with none or up to three or four weaker folds because the soft parts, radulae, and opercula posterior to it; outer lip almost straight; an- do not appear to differ significantly. He stated terior canal notch deep, bent backwards and that Phalium probably had its origin during forming a strong, siphonal fasciole. the late Eocene in south Asia. Wenz (1941) and Da vies (1971) also reported that Phalium VOLUTILITHES OROCOPIAENSIS n. sp. originated during the Eocene, and they both Figure 3.1, 3.2 reported that Semicassis originated during the Diagnosis.— A narrow Volutilithes with Late Cretaceous (Maastrichtian). strong collabral costae and one prominent Prior to P. (S.) louella n. sp., the undoubted columellar fold with two weaker folds pos- earliest reported species of Phalium (Semi- terior to it. cassis) in North America was P. (S.) tuber- Description.— Fusiform and elongate shell culiformis from late early through early mid- of medium size; spire about 40% of the height; dle Eocene strata ("Domengine Stage") of protoconch missing; teleoconch of at least California (Squires, 1984). The occurrence of seven whorls; whorls angulate with strong, P. (S.) louella from the Maniobra Formation narrow, collabral costae that are equally constitutes the earliest record of this genus/ spaced and extend from suture to suture; su- subgenus in North America. tural ramp narrow, gently sloping; eight col- Material.— Two nearly complete speci- labral costae on each spire whorl, eight or mens. nine on body whorl; shoulder angle more Repository. — Holotype, LACMIP 7166, prominent on later whorls; on penultimate LACMIP 7167. whorl, collabral costae are nodose at shoulder Occurrence.— Both specimens were ob- whereas on body whorl they are spiniform; tained from the early Eocene "Capay Stage" on body whorl, collabral costae extend prom- portion of the Maniobra Formation from a inently to neck area; some very faint spiral thin bed approximately 57 m above the base riblets on basal portion of body whorl; col- of the formation, at CSUN locality 665. umella with one prominent fold and one to 860 RICHARD L. SQUIRES AND DA VID M. ADVOCATE

two weaker folds posterior to it; aperture nar- Material. — One nearly complete adult row; outer lip broken or obscured; siphonal specimen and one partial adult specimen. fasciole fairly strong; anterior canal missing. Repository. — Holotype, LACMIP 7168; Comparison.— The new species is most paratype, UCLA 48438. similar to Volutilithes muricinus (Lamarck, Occurrence.— Both specimens were ob- 1802, p. 477) from the middle Eocene (Lute- tained from the early Eocene "Capay Stage" tian Stage), Paris Basin, France. Volutilithes portion of the Maniobra Formation from a muricinus has been further described and/or 30 cm thick bed approximately 57 m above illustrated by Deshayes (1835, p. 697, PI. 91, the base of the formation, at CSUN locality figs. 18, 19; PI. 93, figs. 3, 4; PL 94, figs. 3, 662 (which is equivalent to UCLA locality 4), Cossmann (1899, PI. 6, fig. 1), Cossmann 3779). and Pissarro (1910-1913, PI. 43, fig. 204-1), Etymology. — This species is named for the Wenz (1943, fig. 3773), and Pomerol (1982, Orocopia Mountains in which the Maniobra fig. 3.16-3.19). Formation crops out. Volutilithes orocopiaensis n. sp. differs from UCLA specimen 29199 of V. muricinus from Class Linne, 1758 Chaumont-en-Vexin (Oise), France, and Subclass Neumayr, 1884 UCMP specimen B-5440 of V. muricinus Order VENEROIDA H. and A. Adams, 1856 from Damery, Marne, France, in the follow- Superfamily GLOSSACEA Gray, 1847 ing features: a narrower shell; a less inflated Family Gray, 1847 body whorl; and, more strongly protruding Genus GLOSSUS Poli, 1795 collabral costae on the spire whorls. Voluti- Type species.—By monotypy, Glossus ru- lithes orocopiaensis also has a narrow, gently bicundus Poli, 1795 (—Cardium humanum sloping sutural ramp whereas V. muricinus Linne, 1758), Recent, Western Europe and has a broad, fairly steep sloping, sutural ramp. Mediterranean. Volutilithes torreyensis Givens, 1978, is the only other reliably reported species of this Subgenus MEIOCARDIA genus from the Western Hemisphere, and it H. and A. Adams, 1857 is from the early middle Eocene Ardath Shale near San Diego, California. Volutilithes oro- Type species.—By subsequent designation copiaensis n. sp. differs from V. torreyensis (Stoliczka, 1870), Meiocardia moltkiana in the following features: much more prom- "Spengler" (=Chama moltkiana Gmelin, inent nodes on the shoulder of the body whorl; 1791), Recent, East Indies. spiral ribs only on basal portion of the body Diagnosis. — Equivalved shell, inflated, whorl rather than over the entire surface of subtrigonal shape; prosogyrate beaks in an- the shell; and, only two to three columellar terior half, spirogyrate umbones, lunular area folds rather than five. In addition, V. oro- depressed, no escutcheon, nymph prominent copiaensis has no folds anterior to the most and long; ligament external, attached in deep prominent columellar fold, whereas V. tor- groove; hinge teeth thin, elongate, horizontal reyensis does have a single fold there. instead of vertical, with two lamellar cardi- Discussion. — The basis of modern taxo- nals in each , variable in form, parallel, nomic work on the Volutilithinae is the ar- separated by a lateral groove; ridge-like pos- ticle by Pilsbry and Olsson (1954). Most terior lateral tooth near posterior margin in workers now assign Volutilithes to the both valves; adductor scars equal, valve mar- subfamily Volutilithinae rather than Volu- gins internally smooth; integripalliate pallial tinae. line; posterior margin of shell bounded by a As mentioned by Givens (1978), Voluti- sharp carina; ornament of commarginal ribs. lithes is typical of the Old World Tethyan paleobiogeographic province, where it occurs GLOSSUS (MEIOCARDIA) SUSUKII n. sp. in strata of Late Cretaceous through late Figure 3.3-3.5 Eocene age. The occurrence of Volutilithes Diagnosis. — Small Meiocardia with a wide orocopiaensis n. sp. from the Maniobra For- concave, posterior carina; entire shell exte- mation constitutes the earliest record of this rior finely ribbed. genus in North America. Description. — Equivalved shell subtrigo- NEW EOCENE MOLLUSKS FROM CALIFORNIA 861

FIGURE 3 — 1, 2, Volutilithes orocopiaensis n. sp., holotype, LACMIP 7168, CSUN loc. 662, x 1.2. 3- 5, Glossus (.Meiocardia) susukii n. sp., holotype, UCLA 48427, CSUN loc. 662. 3, left valve, x2; 4, oblique posterior view of left valve, x 1.8; 5, left valve hinge line, x4. nal, moderately inflated, and of small size; p. 72, PL 13, figs. 19-22) possesses. Meio- prosogyrate beaks in anterior half; beak in cardia colombiana is the only other reported left valve incipiently coiled; right valve beak species of Glossus (Meiocardia) in the west- and umbo area obscured; nymph long; two ern Americas. parallel, horizontal, lamellar cardinals in left Discussion.—Meiocardia has been report- valve separated by a lateral groove; posterior ed from strata of Paleocene through Recent lateral tooth area missing; right valve den- age in Europe, Middle East, India, and Indo- tition features obscured; posterior margin of Pacific (Keen and Casey, 1969; Davies, 1971). shell, from beak to the ventral region, bound- It also occurs in strata as old as Paleocene ed by a sharp, wide, concave carina; orna- age in Alabama (Palmer and Brann, 1965) ment of very fine, very closely spaced, corn- and in strata as old as late Eocene/early Oli- marginal costellae, including carina surface. gocene in Colombia, South America (Clark Comparison.—The new species is most and Durham, 1946). similar to Glossus mediavia (Harris, 1896, p. Glossus (M.) susukii n. sp. is the earliest 66-67, Pl. 6, fig. 5) from the Paleocene (lower reported species of this subgenus on the West Midway Group) of Alabama (Palmer and Coast of North and South America. It should Brann, 1965). It differs from G. mediavia in be noted, however, that according to Saul having commarginal sculpture over the entire (personal commun.), there is an unreported surface of the shell and less inflated valves. species of Meiocardia from the Point Loma Glossus mediavia has a well developed pos- Formation of Late Cretaceous age in the San terior carina and is considered to belong to Diego, California area. Glossus (Meiocardia). Material.—A left valve, nearly complete, Glossus (M.) susukii does not have the with the hinge details exposed, shell surface strongly spirogyrate umbones, the heavy weathered, and sculptured layer missing. Also, rounded undulations on the shell exterior, or a crushed complete specimen. the lack of sculpture on the carina that Meio- Repository. —Holotype, UCLA 48427a; cardia colombiana Clark and Durham (1946, paratype, UCLA 48427b. 862 RICHARD L. SQUIRES AND DA VID M. ADVOCATE

Occurrence. —Both specimens were ob- C. Wilson, Los Angeles County Museum. J. tained from the early Eocene "Capay Stage" Le Renard of the National Institute of Agro- portion of the Maniobra Formation from a nomical Research, Versailles, France, gen- 30 cm thick bed approximately 57 m above erously gave me several specimens of Paris the base of the formation, at CSUN locality Basin Eocene gastropods for comparative 662 (which is equivalent to UCLA locality purposes. 3779). I am most grateful to L. R. Saul for her Etymology. — This species is named for valuable comments on molluscan Takeo Susuki who found the type specimens, and identification. C. R. Givens and L. R. identified them as belonging to Meiocardia Saul reviewed the final version of the manu- (=Miocardia), and reported the earliest oc- script and gave valuable comments and sug- currence of this taxon from the West Coast gestions. of North America (Crowell and Susuki, 1959).

REFERENCES LOCALITIES All localities are California State Univer- ABBOTT, R. T. 1968. The helmet shells of the world (Cassidae). Part 1. Indo-Pacific Mollusca, sity, Northridge (CSUN), northeastern Oro- 2:15-202. copia Mountains, Riverside County, Califor- ADVOCATE, D. M. 1983. Depositional environ- nia (Figure 1). ments of the Eocene Maniobra Formation, northeastern Orocopia Mountains, Riverside 662—2,190 ft elevation along crest of small County, southern California. Unpubl. Master's hill, 137 m (450 ft) south and 31 m (100 thesis, California State University, Northridge, ft) west of the northeast corner of sec. 25, 112 p. T6S, R12E, Canyon SpringNW 7.5' Quad- BERGGREN, W. A., D. V. KENT AND J. J. FLYNN. rangle, 1963. This locality is equivalent to In press. Paleogene geochronology and chro- University of California, Los Angeles lo- nostratigraphy. In N. J. Snelling (ed.), Geochro- nology and the Geological Record. Geological cality 3779, which is equivalent to locality Society of London, Special Paper. F of Crowell and Susuki (1959). BRITISH MUSEUM NATURAL HISTORY. 1975. 665—2,120 ft elevation along east side of British Cenozoic Fossils (Tertiary and Quater- small canyon, 861 m (2,825 ft) north and nary), ed. 5. British Museum of Natural History, 709 m (2,325 ft) west of the southeast cor- London, Publication 540, 132 p. ner of sec. 30, T6S, R13E, Canyon Spring CHEDEVILLE, P. J. 1904a. Description de fossiles S nouveaux du bassin Tertiaire de Paris. Bulletin SW 7.5' Quadrangle, 1963. LACMIf U31$ de la Societe d'etude des Sciences Naturelles 668—2,000 ft elevation in stream bed, 421 d'Elbeuf, 4th ser., 22:101-106. m (1,380 ft) south and 198 m (650 ft) east . 1904b. Liste generale et synonymique des of the northwest corner of sec. 31, T6S, fossiles Tertiaires du bassin de Paris. Bulletin R13E, Canyon Spring SW 7.5' Quadrangle, de la Societe d'etude des Sciences Naturelles 1963. -LAc^UP IUSS d'Elbeuf, 4th ser., supplement, 22:375-438. 671 — 2,040 ft elevation in stream bed, 579 CLARK, B. L. 1942. New middle Eocene gastro- pods from California. Journal of Paleontology, m (1,900 ft) north and 26 m (85 ft) west 16:116-119. of the southeast corner of sec. 31, T6S, AND H. E. VOKES. 1936. Summary of ma- R13E, Canyon Spring SW 7.5' Quadrangle, rine Eocene sequence of western North Amer- 1963. =LACMir IU7& ica. Geological Society of America Bulletin, 47: 851-878. ACKNOWLEDGMENTS AND J. W. DURHAM. 1946. Eocene faunas from the Department of Bolivar, Colombia. Sincere thanks are extended to California Geological Society of America Memoir 16, 126 p. State University, Northridge geology stu- COSSMANN, A. E. M. 1899. Essais de paleocon- dents D. Yamashiro and J. Brown for their chologie comparee, 3. Private publication, Paris, help in collecting the fossils. 201 p. The following people kindly provided the . 1903. Essias de paleoconchologie compa- ree, 5. Private publication, Paris, 213 p. loan of specimens: D. L. Lindberg, Univer- -. 1904. Essais de paleoconchologie compa- sity of California, Berkeley; P. U. Rodda, ree, 6. Private publication, Paris, 148 p. California Academy of Sciences; L. R. Saul, —. 1906a. Essais de paleoconchologie com- University of California, Los Angeles; and E. paree, 7. Private publication, Paris, 261 p. NEW EOCENE MOLLUSKS FROM CALIFORNIA 863

. 1906b. Catalogue illustre des coquilles fos- ifornia. Pacific Section, Society of Economic Pa- siles de l'Eocene des environs de Paris. Annales leontologists and Mineralogists. de la Societe Royale Malacologique de Belgique, GLIBERT, M. 1963. Les Mesogastropoda fossiles Appendice No. 4, 41:186-286. du Cenozoique etranger des collections de l'ln- AND G. PISSARRO. 1910-1913. Iconogra- stitut Royal des Sciences Naturelles de Belgique. phie complete des coquilles fossiles de l'Eocene Part 2, Fossaridae to (included). Brus- des environs de Paris. Societe Geologique de sels. Memoires Institut Royal des Sciences Na- France, Vol. 2, 65 pis., Paris. turelles de Belgique, ser. 2, Vol. 73, 154 p. CROWELL, J. C. AND T. SUSUKI. 1959. Eocene HANNA, G. D. 1924. Rectifications of nomen- stratigraphy and paleontology, Orocopia Moun- clature. California Academy of Sciences Pro- tains, southeastern California. Geological So- ceedings, 4th ser. 13:151-186. ciety of America Bulletin, 70:581-592. AND L. G. HERTLEIN. 1949. Two new species CURRY, D. ET AL. 1978. A correlation of Tertiary of gastropods from the middle Eocene of Cali- rocks in the British Isles. Geological Society of fornia. Journal of Paleontology, 23:392-394. London Special Report 12, 72 p. HARRIS, G. D. 1896. The Midway Stage. Bul- DAVIES, A. M. 1971. Tertiary Faunas. Vol. 1. letins of American Paleontology, 1:1-157. The Composition of Tertiary Faunas. Revision INGRAM, W. M. 1942. Type fossil Cypraeidae of by F. E. Eames. American Elsevier Publishing North America. Bulletins of American Paleon- Company, New York, 571 p. tology, 27(104): 1-32. . 1975. Tertiary Faunas. Vol. 2. The Se- IREDALE, T. 1917. More molluscan name- quence of Tertiary Faunas. Revision by F. E. changes, generic and specific. Malacological So- Eames and R. J. G. Savage. George Allen and ciety of London Proceedings, 12:322-330. Unwin, London, 447 p. KANNO, S. 1973. Japanese Tertiary cassids (Gas- DELPEY, G. 1941. Histoire du genre Campanile. tropoda) and their related mollusks from the Annales de Paleontologie, 29:3-25. west coast of North America. Tohoku Univer- DESHAYES, G.P. 1824-1837. Description des co- sity Science Reports, ser. 2 (Geology), Special quilles fossiles des environs de Paris, 2. Private Volume 6 (Hatari Memorial Volume), p. 217— publication, Paris, 780 p. 233. . 1866. Description des animaux sans ver- KAPPELER, K. A., R. L. SQUIRES AND A. E. FRITSCHE. tebres decouverts dans le bassin de Paris. Vol. 1984. Transgressive marginal-marine deposits 3 of text, Vol. 2 of atlas. J. B. Bailliere et Fils, of the Avenal Sandstone, Reef Ridge, central Paris, 667 p. (text), 107 pis. (atlas). California, p. 9-27. In J. R. Blueford (ed.), Krey- DICKERSON, R. E. 1914. Fauna of the Martinez enhagen Formation and Related Rocks. Pacific Eocene of California. University of California Section, Society of Economic Paleontologists and Publications in Geological Sciences, 8:61-180. Mineralogists. . 1916. Stratigraphy and fauna of the Tejon KEEN, A. M. AND H. BENTSON. 1944. Checklist Eocene of California. University of California of California Tertiary marine Mollusca. Geo- Publications in Geological Sciences, 9:363-524. logical Society of America Special Papers, 56: DIXON, F. 1850. The Geology and Fossils of the 1-280. Tertiary and Cretaceous Formations of Sussex. AND R. CASEY. 1969. Superfamily Glos- Taylor, London, 422 p. sacea Gray, 1847, p. 657-664. In R. C. Moore DOUVILLE, H. 1904. Paleontologie, mollusques (ed.), Treatise on Invertebrate Paleontology, (N) fossiles, p. 191-380. In J. de Morgan, Mission Mollusca 6. Geological Society of America and scientifique en Perse, Vol. 3, pt. 4. E. Leroux, University of Kansas Press, Lawrence. Paris. LAMARCK, J. B. 1802. Memoire sur les fossiles GABB, W. M. 1864. Description of the Creta- des environs de Paris. Annales du Museum Na- ceous fossils, p. 55-243. In F. B. Meek and W. tional d'Histoire Naturelle, 1:299-312, 383-391, M. Gabb, Palaeontology of California, Geolog- 474-479. ical Survey of California, Vol. 1, Palaeontology. . 1804. Memoire sur les fossiles des environs Caxton Press, Philadelphia. de Paris. Annales de Museum National d'His- GIVENS, C. R. 1974. Eocene molluscan biostra- toire Naturelle, 3, 4, 5, variously paged. tigraphy of the Pine Mountain area, Ventura . 1805. Memoire sur les fossiles des environs County, California, University of California de Paris. Annales du Museum National d'His- Publications in Geological Sciences, 109:1-107. toire Naturelle, 6:117-126, 214-228. . 1978. An occurrence of the Tethyan genus LHOMME, L. 1904. Coquilles fossiles trouvees en Volutilithes (Gastropoda: Volutidae) in the 1903 dans les sables de Saint-Gobrain (Ypre- Eocene of California. Journal of Paleontology, sian). Feuille des Jeunes Naturalistes Paris, no. 52:104-108. 401, p. 103-106. AND M. P. KENNEDY. 1979. Eocene mol- NELSON, R. N. 1925. A contribution to the pa- luscan stages and their correlation, San Diego leontology of the Martinez Eocene of California. area, California, p. 81-95. In P. L. Abbott (ed.), University of California Publications in Geo- Eocene Depositional Systems, San Diego, Cal- logical Sciences, 15:397-466. 864 RICHARD L. SQUIRES AND DA VID M. ADVOCATE

PALMER, K. V. W. 1967. A comparison of certain type gastropods. Academy of Natural Sciences Eocene molluscs of the Americas with those of of Philadelphia Proceedings, 78:287-447. the western Tethys, p. 183-193. In C. G. Adams VOKES, H. E. 1935. The genus Velates in the and D. V. Ager (eds.), Aspects of Tethyan Bio- Eocene of California. University of California geography. Systematics Association Publica- Publications in Geological Sciences, 23:381-390. tion, no. 7. . 1939. Molluscan faunas of the Domengine . 1977. The unpublished velins of Lamarck and Arroyo Hondo Formations of the California (1802-1809) illustrations of fossils of the Paris Eocene. Annals of the New York Academy of Basin Eocene. Paleontological Research Insti- Sciences, 38:1-246. tution, Ithaca, New York, 67 p. WENZ, W. 1940. Gastropoda: Allgemeiner Teil AND D. C. BRANN. 1965. Catalogue of the und Prosobranchia, p. 721-960. In O. H. Schin- Paleocene and Eocene Mollusca of the southern dewolf (ed.), Handbuch der Palaozoologie, Band and eastern United States. Bulletins of Ameri- 6, Gastropoda, Teil 4. Gebriider Borntraeger, can Paleontology, 48(218):1-1057. Berlin. PILSBRY, H. A. AND A. A. OLSSON. 1954. Systems -. 1941. Gastropoda: Allgemeiner Teil und of the Volutidae. Bulletins of American Paleon- Prosobranchia, p. 961-1200. In O. H. Schin- tology, 35(152): 1-36. dewolf (ed.), Handbuch der Palaozoologie, Band POMEROL, C. 1982. The Cenozoic Era (Tertiary 6, Gastropoda, Teil 5. Gebriider Borntraeger, and ). Ellis Horwood Limited, Berlin. Chichester, England, 272 p. . 1943. Gastropoda: Allgemeiner Teil und QUOY, J. R. AND J. P. GAIMARD. 1834. Voyage Prosobranchia, p. 1200-1506. In O. H. Schin- de la corvette L'Astrolabe. Vol. 3, pt. I. Paris. dewolf (ed.), Handbuch der Palaozoologie, Band SAUL, L. R. 1983. Notes on Paleogene turritellas, 6, Gastropoda, Teil 6. Gebriider Borntraeger, venericardias, and molluscan stages of the Simi Berlin. Valley area, California, p. 71-80. In R. L. Squires WRIGLEY, A. 1934. English Eocene and Oligo- and M. V. Filewicz (eds.), Cenozoic Geology of cene Cassididae, with notes on the nomencla- the Simi Valley Area, Southern California. Pa- ture and morphology of the family. Malaco- cific Section, Society of Economic Paleontolo- logical Society of London Proceedings, 21:108- gists and Mineralogists. 130. SCHENCK, H. G. 1926. Cassididae of western . 1940. The English Eocene Campanile. America. University of California Publications Malacological Society of London Proceedings, in Geological Sciences, 16:69-98. 24:97-112. SCHILDER, F. A. 1932. Cypraeacea. Fossilium ZINSMEISTER, W. J. 1974. Paleocene biostratig- Catalogus I, pt. 55, 276 p. raphy of the Simi Hills, Ventura County, Cali- . 1966. The higher taxa of cowries and their fornia. Unpubl. Ph.D. dissertation, University allies. The , 9:31-35. of California, Riverside, 236 p. . 1967. The generic classification of cowries. . 1983. Late Paleocene ("Martinez Provin- The Veliger, 10:264-273. cial Stage") molluscan fauna from the Simi Hills, SQUIRES, R. L. 1983. New mollusks from the Ventura County, California, p. 61-70. In R. L. lower middle Eocene Llajas Formation, south- Squires and M. V. Filewicz (eds.), Cenozoic Ge- ern California. Journal of Paleontology, 57:354- ology of the Simi Valley Area, Southern Cali- 362. fornia. Pacific Section, Society of Economic Pa- . 1984. Megapaleontology of the Eocene leontologists and Mineralogists. Llajas Formation, Simi Valley, California. Los Angeles County Natural History Museum, Con- MANUSCRIPT RECEIVED 25 SEPTEMBER 1984 tributions in Science 350, 76 p. REVISED MANUSCRIPT RECEIVED 7 FEBRUARY 1985 STEWART, R. B. 1927. Gabb's California fossil