FAU Institutional Repository

http://purl.fcla.edu/fau/fauir

This paper was submitted by the faculty of FAU’s Harbor Branch Oceanographic Institute.

Notice: ©1987 The Bailey-Matthews Shell Museum. This author manuscript appears courtesy of The Nautilus, a peer-reviewed, not-for-profit quarterly published by the non-profit organization The Bailey-Matthews Shell Museum. The published version is available at http://shellmuseum.org/nautilus/index.html and may be cited as: Mikkelsen, P. M., & Mikkelsen, P. S. (1987). Redescription of Acteocina recta and A. lepta, two species of cephalaspidean gastropods from the western Atlantic. The Nautilus, 101(2), 51-58.

THE NAUTILUS 101(2):51-58, 1987 Page 51

Redescription of Acteocina recta and A. lepta, Two Species of Cephalaspidean Gastropods from the Western Atlantic

Paula M. Mikkelsen Paul S. Mikkelsen Harbor Branch Oceanographic Institution, Inc. 5600 Old Dixie Highway .. Ft. Pierce, FL 33450-9719, USA

ABSTRACT ANSP, Academy of Natural Sciences of Philadelphia, Philadelphia, PA. Acteocina recta (Orbigny, 1841) and A.lepta Woodring, 1928, both from the Western Atlantic, are redescribed on the basis BM(NH), British Museum (Natural History), London. of type material and other specimens from museums and pri­ Coovert Collection, Gary A. Coovert, Dayton, OR. vate collections. Acteocina recta, for which a lectotype is des­ Edwards Collection, Amy L. Edwards, University of ignated, is characterized by its generally small (1-2 mrn), thin Georgia, Athens, GA. shell, spiral striae, low spire, double-keeled shoulder, and ta­ Finlay Collection, C. John Finlay, Palm Bay, FL. pered protoconch, indicative of planktotrophic larval devel­ FSBC I, Florida Department of Natural Resources, opment. It ranges from eastern Florida to Texas, and through­ Bureau of Marine Research, St. Petersburg, FL. out the Caribbean to Brazil. Acteocina lepta was originally HMNS, Houston Museum of Natural Science, Hous­ described as a Plio-Pleistocene fossil from Jamaica. It is thick­ ton, TX. shelled and spirally striate, with a low spire, double-keeled IRCZM, Indian River Coastal Zone Museum, Harbor shoulder, and bulbous protoconch, indicative of non-plankto­ trophic larval development; adults are 2-5 mm in length. In Branch Oceanographic Institution, Ft. Pierce, FL. the Recent fauna, it ranges from Bermuda and North Carolina Keeler Collection, James H. Keeler, Tallahassee, FL. to Louisiana, and throughout the Caribbean to Brazil. Lee Collection, Harry G. Lee, Jacksonville, FL. LIU, Southampton College (Long Island University), Southampton, NY. INTRODUCTION MCZ, Museum of Comparative Zoology, Harvard Uni- versity, Cambridge, MA. In the course of studying collections of Western Atlantic MORG, Museu Oceanografico, Rio Grande, Brazil. Acteocina species, numerous morphotypes have been dis­ Redfern Collection, Colin Redfern, Boca Raton, FL. tinguished. Three of these, A. canaliculata (Say, 1826), UNC-IMS, Institute of Marine Sciences, University of A. candei (Orbigny, 1841), and A. atrata Mikkelsen and North Carolina, Morehead City, NC. Mikkelsen, 1984, have already been recognized as valid USNM, National Museum of Natural History, Smith­ species (Mikkelsen & Mikkelsen, 1984). Two others, A. sonian Institution, Washington, DC. recta (Orbigny, 1841) and A.lepta Woodring, 1928, have Williams Collection, Peggy Williams, Sarasota, FL. often been misidentified in collections, and have fre­ Worsfold Collection, Jack Worsfold, Freeport, Baha­ quently been confused with each other. The present pa­ mas. per redescribes the last two species on the basis of type In "Material Examined" sections, an "L" following specimens and other live- and dead-collected material, the number of specimens indicates that at least one of and redefines their geographic distributions. the specimens in the lot was live-collected and contained soft parts; an "E" indicates that all specimens were empty shells. MATERIALS AND METHODS Shell terminology is after Smith (1967:758-760) and Knight (1952:7-9); radular terminology is after Bertsch Dried and wet-preserved specimens from the following (1977:110-111). Radulae and gizzard plates were ex­ museums and private collections were utilized to deter­ tracted and prepared for light microscopy using the mine geographic and bathymetric distributions of these method previously described (Mikkelsen & Mikkelsen, species: 1984; Mikkelsen, 1985). Page 52 THE NAUTILUS, Vol. 101, No.2

1

..

. .

Figures 1-4. Acteocina recta. 1. Syntypes, BM(NH ) 1854.10.4.16. Left 1.41 mm (lectotype), center 1.85 mm (paralectotype), right 1.76 mm (paralectotype). 2. Adult shell from off Ft. Pierce , Florida, 1.62 mm. 3. Specimen in figure 2, oblique view of P. M. Mikkelsen and P. S. Mikkelsen, 1987 Page 53

SYSTEMATIC RESULTS remnants on their dorsal surfaces. The locality given on the label is "Antilles." Acteocina Gray, 1847 The smallest syntype (figure 1, left), being the best Acteocina recta (Orbigny, 1841) representative of the species-specific characters, is here (figures 1-6) designated as lectotype for Acteocina recta. The re­ maining two specimens (figure 1, center and right) are Bulla recta Orbigny, 1841:131; 1842: pI. 4 bis, figs. 17-20. designated as paralectotypes. ) . Material examined: Syntypes: 3 specimens [lectotype Diagnosis: Teleoconch thin-walled, cylindrical, with fine (1.41 mm), 2 paralectotypes (1.85 mm, 1.76 mm frag­ spiral striae throughout its length. Shoulder with rounded ment)], BM(NH) 1854.10.4.16. Other material: 632 keel adjacent to suture and sharp keel at shoulder; 2 keels specimens (ANSP, HMNS, LIU, MCZ, MORG, USNM, separated by concave trough. Protoconch tapered, in­ Worsfold Collection), including the following as repre­ dicating planktotrophic development. Lateral radular sentative vouchers: FLORIDA: Off Ft. Pierce: LlL, IRCZM teeth each with a wing-like expansion bearing a single 065:02411, 065:M0063 (microslide with radula and giz­ row of denticles; rachidian teeth with 3 robust denticles zard plates); 2L, USNM 859080; 2L, USNM 859081; 6L, per half. Unpaired gizzard plate T-shaped. ANSP A11629; 6L, BM(NH) 1986149 (including mi­ croslide with radula and gizzard plates).-Bahia Honda Distribution: St. Lucie County, eastern Florida, to Key: IE, USNM 358296.-LoUISIANA: South Pass: 30E, southern Texas; Bahamas; Greater and Lesser Antilles; HMNS 9222.-TEXAS: Southeast of Freeport: 15L, HMNS Atlantic Panama; southeastern Brazil. Recorded living at 8122.-North of Port Isabel: 9E, HMNS 8151.-GREATER depths of 33-44 m; empty shells collected from 2-128 m. ANTILLES: Northwestern Cuba: IE, USNM 358229.­ Description: The orthostrophic, dextral teleoconch of Cayman Islands: IE, ANSP 295944.-Haiti: 2E, USNM Acteocina recta (figure 2) is cylindrical with nearly par­ 859087.-BAHAMAS: North of Abaco: IE, MCZ 294082.­ allel sides, and has fine spiral striae. Two to three whorls LESSER ANTILLES: British Virgin Islands: 5L, ANSP are typical of adult (1-2 mm) specimens. The aperture 351676.-Antigua: IE, USNM 859088; 6E, ANSP 8220.­ is narrow (i.e., less than 1J4 of the shell width), paralleling West Grenada: IE, ANSP 296955.-CENTRAL AMERICA: the side of the body whorl, and flaring anteriorly. The Belize: 6E, ANSP 285386.-Guatemala: IE, ANSP columella, although "toothless" as Orbigny (1841) stated, 76460.-Panama: 2E, ANSP 200034.-S0UTH AMERICA: bears a single weak fold. The shell walls are thin and South Bahia, off eastern Brazil: IE, MORG 20.110 (spec­ transparent in fresh material. The shoulder (figure 3) is imen subsequently lost). double-keeled; a sharp keel at the shoulder is separated Original description: Orbigny (1841:131) originally de­ from a rounded keel adjacent to the suture by a narrow scribed Bulla recta from the Antilles as "oblong, straight, concave trough of varying depth. The rounded keel and cylindrical, uniform throughout its length, slender, frag­ concave trough are crossed by strong axial wrinkles. The ile, shining, displaying nevertheless, under magnifica­ spire is nearly flat in specimens under 2 mm; in larger tion, signs of transverse striations. Spire projecting, very individuals (to 2.5 mm), spire height is typically less than short, strongly channeled at the suture. Aperture linear, 20% of the shell length. The periostracum is thin and straight behind, suddenly enlarging at the front, colu­ transparent. mella simple, without teeth. Color uniformly white." He The smooth, hyperstrophic protoconch (figure 4) is distinguished the species by its strongly cylindrical shape tapered and similar in shape to that of Acteocina ca­ and spiral striations, and described its protoconch as naliculata (Say, 1826), which was shown to indicate "transverse to the spiral axis," or hyperstrophic. planktotrophic larval development (Mikkelsen & Mik­ kelsen, 1984: fig. 3, e-g). Type material: The type material of Bulla recta (figure The radular formula of Acteocina recta is 1-R-1, with 1) consists of three specimens, all originally glued to a 8-14 radular rows in adults (n = 6). The rachidian teeth strip of black paper. The smallest specimen (1.41 mm (figure 5, R) are centrally notched, with each rounded length), still glued to the paper, has an intact protoconch, half bearing three (rarely four) sharply pointed, robust highly evident spiral striae, and has retained its trans­ denticles. The lateral teeth (figure 5) are sickle-shaped parency. A second specimen (1.85 mm length), although and unicuspid, with the cusp bearing a wing-like expan­ more worn than the first, shows fine spiral striae and a sion supporting one row of 4-6 denticles. A blunt basal

.> • slightly glossy surface. The third specimen (1.76 mm tubercle is present for articulation with adjoining lateral length), consisting of a fragmented body whorl, is of a teeth. size and shape to be positively identified as A. recta. The Three calcareous gizzard plates are present (figure 6): latter two specimens are loose, but have glue and paper a "pair" of non-identical, but similarly elongated, plates

shoulder. Scale bar = 40 !Lm. 4. Specimen in figure 2, protoconch showing tapered, planktotrophic-type morphology. Scale bar = 40 urn, Page 54 THE NAUTILUS, Vol. 101, No.2

concholog y in having a larger, more robust shell with a 5 deeply channeled suture and bulbou s protoconch. Caution must be used in dealing with small specimens of Acteocina candei (Orbigny, 1841), which are often thin-shell ed, low-spired and lack distinct subsutural sculptural bands, thus resembling specim ens of A. recta. 1£-' The form er species may be distinguished in these cases by the absence of spiral striae.

Acteocina lepta Woodring, 1928 (figures 7-13) 7 Acteocina lepta Woodring, 1928:121, pl. 2, fig. 5. Retu sa candei (Orbigny, 1841). Warmke and Abbott, 1962: 143, pI. 27g; Rice and Kornicker, 1965:129, pl. 8, fig. 10. @.R.. l • ...... Acteocina recta (Orbigny, 1841). Peile, 1926:85 [ref. ANSP 141560 (voucher specimens )]. Tornat ina candei (Orbigny, 1841). Rehder, 1981:635, fig. 356. (jV ? Tornatina cylindrica Emmons, 1858:181, fig. 182. Material examined: Holotype: 3.78 mm,USNM 369320. Other material: 2,302 specimens (ANSP, FSBC I, HM S, IRCZM, LIU, MCZ, MORG,UNC-IMS, USNM, and collections of Coovert, Edwards, Finlay, Keeler , Lee, Figures 5-8. Radulae and gizzard plates. Acteocina recta: 5. Redfern , Williams, Worsfold ) including the following as Two rachidian (R) and two lateral teeth . Scale bar = 10 ~m . representative vouchers: BERMUDA: 24E, ANSP 141560.- ~m . 6. Gizzard plates. Scale bar = 100 A. lepta: 7. Two ra­ ORTH CAROLI A: Off Cape Hatteras: 1L,USNM chidian (R) and two lateral teeth. Scale bar = 10 ~m. 8. Gizzard 329930.-0ff Cape Lookout: 3L,U C-IMS 9858.1-3; plates. Scale bar = 100 ~m . 2L, IRCZM 065:02056, 065:M0057 (microslide with rad­ ula and gizzard plates ).-SoUTH CAROLINA: IE, IRCZM opposes a larger "unpaired" plate. The unpaired plate 065:01930.-GEORGIA: IE, Edwards Collection.-FLORI­ is most dorsal in the crawling and is distinctly DA: Off St. Lucie County: IE, FSBC I 26258.-0ff Palm T-shaped (n = 5). Beach: 3E, ANSP 359158.-0ff Miami: 9E, USNM 859089.-Key Largo : 18E, ANSP 336230.-Key West: Remarks: Since its original description, Acteocina recta 2L, USNM 859090.-0ff Sanibel: 1L, MCZ 245062.­ has appeared in the literature mainly as an undiscussed Off Tampa: 2E, ANSP 358045.-0ff Cape San BIas: 3E, member of various Recent faunal lists (e.g., Gabb, 1873, USNM 323422.-LoUlSIANA: Off Cameron: 3E, HMNS 1881; March , 1875; Guppy, 1876; Arango y Molina, 1878; 8161.-GREATER ANTILLES: Northern Cuba: 2E, Finlay Dall, 1889, 1903b; Smith , 1890; Ihering, 1915; Maury, Collection.-Southeastern Cuba: IE, USNM 383696.­ 1922;Johnson, 1934; Lange de Morretes, 1949; Coomans , Jamaica: 27E, USNM 859091.-Cayman Islands: 5E, 1963; Marcus & Marcus, 1964; Abbott, 1974). One such ANSP 296098.-Dominican Republic: 2E , USNM Bermudan record (Peile, 1926) has been found , by ex­ 807258.-Western Puerto Rico: IE, USNM 859092.­ amination of voucher specimens (A SP 141560; see A. BAHAMAS: Greater Abaco Island : 3E, ANSP 357901.­ lepta synonymy), to be A. lepta. Pilsbry (1895) and Ver­ Bimini Islands: 9E,USNM 859093.-Andros Island: 548E, rill and Bush (1900) figured A. recta, gave brief synon­ USNM 859094.-Lesser Antilles: Barbados: 2E, USNM ymies, and/or reiterated previous descriptions. In the 500361.-CENTR AL AMERICA: Yucat an : IE, USNM fossil literature, A. recta has been recorded from the 667674.-S0UTH AMERICA: Northern Brazil: 8E, MORG Miocene of Santo Domingo (Gabb, 1873; Maur y, 1917, 22.365. 1922), the Oligocene of Jamaica (Dall, 1903a), and the Miocene and Pliocene of Costa Rica (Olsson, 1922, and Original description: Acteocina lepta was originally Gabb , 1881, respectively). None of these previous rec­ described as a fossil from Bowden, Jamaica: "shell small, . \. ords, with the exception of Peile (1926), have been ver­ slender, tightl y coiled, subcylindrical, body whorl ta­ ified through specimen examination, although all fall pering gentl y at base. Nuclear whorls forming a large within the verified geographic range of the species. tip. Anal fasciole concav e, bearing axial puckers, bound­ Some workers (Dall, 1889; Maury, 1917; Olsson, 1922; ed by sharp-edged ridges. Middle of outer lip slightly Woodrin g, 1928) have cited Tornatina coixlacryma constricted. Umbilical groove narrow, deep " (Woodring, Guppy, 1867, from the Jam aican Miocene, as a synonym 1928:121). Although presumed by Woodring to be Late (in whole or in part) of Act eocina recta . However, the Middle Miocene, Blow (1969) and Robinson and Lamb neotype of T. coixlacryma (USNM 369322, designated (1970) have shown the type locality to be Pliocene to by Woodrin g, 1928) differs markedly from A. recta in Early Pleistocene in age. P. M. Mikkelsen and P. S. Mikkelsen, 1987 Page 55

9

) I

, .

.' :

j'

Figures 9-13. Acteocina lepta. 9. Holotype, 3.78 mm , USNM 369320. 10. Adult shell from Cuba, 4.50 mm. 11. Specimen in figure 10, oblique view of shoulder. Scale bar = 100 Jlm . 12, 13. Specimen in figure 10, protoconch showing bulbous, non­ planktotrophic morphology. Scale bars = 40 Jlm. Page 56 THE NAUTILUS, Vol. 101, No.2

Type material: The holotype of Acteocina lepta (figure halves of the tooth. The lateral teeth (figure 7) are sickle­ 9), although worn, is in generally good condition and has shaped and unicuspid, with the cusp bearing a wing-like an intact protoconch. A bored hole with worn edges is expansion supporting one row of 10-12 denticles. A blunt, on the ventral surface of the body whorl. No sculptural basal tubercle is present for articulation with adjoining details can be discerned on the shell surface, except for lateral teeth. distinct axial wrinkles on the shoulder. The three subequal calcareous gizzard plates (figure 8) consist of a rounded heart-shaped "unpaired" plate, Diagnosis: Teleoconch thick-walled, porcellaneous, cy­ , ( and two elongated, nonidentical "paired" plates (n = 3). lindrical, finely spirally striate throughout its length. Shoulder with rounded, elevated keel adjacent to suture, Remarks: Acteocina lepta has been cited in the liter­ plus sharp keel at shoulder, separated by a slightly con­ ature only once since its original description, from the •• cave, axially wrinkled area. Protoconch well-protruded Middle Miocene of Santa Rosa, Veracruz, Mexico (Per­ and bulbous, indicating non-planktotrophic develop­ rilliat, 1974). It has not been previously recorded as part ment. Lateral radular teeth each with a wing-like ex­ of any Recent fauna. The results of our previous work pansion bearing a single row of denticles. Rachidian teeth on the type species A. canaliculata (see Mikkelsen & with robust base, median buttress, and fine denticles. Mikkelsen, 1984) allow the genus Acteocina to be used Unpaired gizzard plate heart-shaped. for this, and other, extant species. Numerous museum lots of Acteocina lepta have been Distribution: Bermuda; North Carolina to the Florida misidentified as A. recta. This may stem from a mis­ Keys and to Louisiana; throughout the Caribbean, in­ leading statement by Woodring (1928:121) who origi­ cluding the Greater and Lesser Antilles, the Bahamas, nally described A. lepta as "the Bowden representative Yucatan, and to northern Brazil. Plio-Pleistocene to Re­ of" and "smaller than" the living A. recta. cent. Recorded living at depths of 7-226 m; empty shells Acteocina lepta is similar in general appearance to collected from 2-457 m. Tornatina persimilis Dall, 1895, from the Oligocene of Description: The orthostrophic, dextral teleoconch of Florida, as noted by Woodring (1928). However, the Acteocina lepta (figure 10) is cylindrical, with nearly latter species (holotype, 3.02 mm, USNM 112607) has a parallel sides, and is finely spirally striate. The shells are tapered, planktotrophic-type protoconch and completely rather thick, giving a porcellaneous appearance to av­ lacks spiral striations. erage-sized (3-5 mrn) specimens. The columella bears a The original figure of the North Carolina Miocene single strong fold. In live-collected or fresh-dead mate­ species Tornatina cylindrica Emmons, 1858, is ex­ rial, a thin, light yellow periostracum is evident. The tremely similar to Acteocina lepta. A search for type shoulder (figure 11) is sharply keeled, with a second material of Emmon's species has been unsuccessful, mak­ elevated keel just below the suture. Between these keels, ing determination of protoconch morphology and other the rather wide slope is slightly concave and axially wrin­ critical features impossible. The original description is kled. The spire is generally very low, usually 7-9% (max­ inadequate to distinguish it from other species, therefore, imum 13%) of the total length. T. cylindrica must be considered a nomen dubium. The smooth, hyperstrophic protoconch (figures 12, 13) Acteocina lepta bears close resemblance to Tornatina is typically well-protruded above the first teleoconch liratispira E. A. Smith, 1872, the sole conchological dif­ whorl. It is bulbous and similar in shape to that of Ac­ ference being protoconch morphology. The four syn­ teocina atrata Mikkelsen and Mikkelsen, 1984 (Mikkel­ types of the latter species [BM(NH) 1860.5.2.29] were sen & Mikkelsen, 1984: fig. 8, e-g). This type of proto­ examined; one of the four specimens was found to be A. conch has been observed in at least ten species of candei (Orbigny). As no live-collected specimens of T. cephalaspids in the Western Atlantic alone, and is known liratispira were available for dissection, radular and giz­ in two, including A. atrata, to reflect capsular meta­ zard plate morphologies remain unknown. Determina­ morphic (= direct) larval development (personal obser­ tion of its proper generic placement and relationship with vation). However, some recent workers (Turner et al., A. lepta must therefore await further study. Tornatina 1985) have surmised that prosobranch protoconchs of liratispira is here reported from the Bahamas, the Great­ this same general size and morphology indicate lecitho­ er and Lesser Antilles, and the northern coast of Brazil, trophic (= non-feeding planktonic) development. Given at depths ranging from 35 to 106 m. this apparent discrepancy, the best we can infer from Acteocina lepta has been figured several times in the the available evidence is that A. lepta probably has non­ literature as A. candei (Orbigny) (Warmke & Abbott, planktotrophic development. 1962; Rice & Kornicker, 1965; Rehder, 1981). The radular formula of Acteocina lepta is l-R-l with about 16 rows in adult specimens (n = 3). The rachidian DISCUSSION teeth (figure 7, R) are centrally notched with each half bearing 6-9 fine, sharply pointed denticles. The base of Morphological characteristics of Acteocina recta and A. the rachidian is robust (staining dark pink in acid fuchsin) lepta are summarized in table 1. and extends along the center of the tooth in the form of Extreme caution is advised when identifying speci­ a triangular buttress. The apex of this buttress meets the mens of these and other species of Acteocina sensu lato. approximate center of the indentation between the two Key characters include shell shape and general sculpture, P. M. Mikkelsen and P. S. Mikkelsen, 1987 Page 57

Table 1. Distinguishing characteristics of Acteocina recta and A. lepta.

A. recta A. lepta Shell length 1-2 mm 3-5 mm Shell shape cylindrical, parallel sides cylindrical, nearly parallel sides Spire height flat to low «20%) flat to low (7-13%) Sutural keel rounded sharp, elevated • • Trough between shoulder and sutural keels narrow, concave wide, concave Shell walls thin, transparent thick, porcellaneous Columella weak fold strong fold ,. Periostracum thin, transparent thin, light yellow Protoconch tapered bulbous Inferred type of larval development planktotrophic non-planktotrophic Lateral tooth denticles 4-6 10-12 Rachidian tooth denticles 3 per half 6-9 per half Rachidian buttress not present present Unpaired gizzard plate T-shaped heart-shaped

shoulder sculpture, type of protoconch, radula, and giz­ the manuscript. J. Piraino (SMSLP) and T. Smoyer (HBOl) zard plates. Spiral striae are often exceedingly fine and assisted with SEM and light photography, respectively. may be imperceptible in wet ti.e., alcoholic) specimens; K. Metzger and C. Browder (HBOI), and the staff of the momentary drying of the shell surface is frequently nec­ Division of Mollusks, USNM, assisted in literature ac­ essary for examination. Worn shells, especially those with quisition. eroded surfaces and/or missing or worn protoconchs are This is Contribution Number 546 of Harbor Branch particularly problematic. All species of Acteocina (and Oceanographic Institution, Inc. other closely related genera) that we have examined thus far are conchologically separable. However, these con­ LITERATURE CITED chological distinctions may be in the protoconch only. A thorough understanding of species-specific shell char­ Abbott, R. T. 1974. American seashells, 2nd ed. Van Nostrand acters, in combination with radular and gizzard plate Reinhold Company, New York, 663 p., 24 pis. characteristics, is essential. Arango y Molina, R. 1878. Contribucion a la fauna malaco­ logica Cubana. Imp. de G. Montiel y Comp., Habana, 280 text p. + 35 index p. ACKNOWLEDGEMENTS Bertsch, H. 1977. The Chromodoridinae nudibranchs from the Pacific coast of America. Part I. Investigative methods The time required to conduct this work was generously and supra-specific . The Veliger 20(2):107-118. allowed by Dr. Robert W. Virnstein (Seagrass Ecosystems Blow, W. H. 1969. Late Middle Eocene to Recent planktonic Analysts, Ft. Pierce, FL) and Mr. John E. Miller [Harbor foraminiferal biostratigraphy. In: Bronnimann, P. and H. Branch Oceanographic Institution (HBOl), Ft. Pierce, H. Renz (eds.), Proceedings of the First International Con­ FL]. Our thanks extend to the following for arranging ference on Planktonic Microfossils, Geneva, 1967. E. J. examination of museum specimens entrusted to their Brill, Leiden, 1:199-421, 54 pis. care: the late Dr. Joseph Rosewater, Mr. Frederick J. Coomans, H. E. 1963. The marine of St. Martin, Collier, and Mr. Warren C. Blow (USNM); Dr. John Lesser Antilles, collected by H. J. Krebs. Studies on the Fauna of Curacao and Other Caribbean Islands 16:59-87. Taylor and Ms. Kathie Way [BM(NH)]; Dr. Robert Rob­ Dall, W. H. 1889. Reports on the results of dredging, under ertson and Ms. Mary A. Garback (ANSP); Dr. Kenneth the supervisionof Alexander Agassiz, in the Gulf of Mexico J. Boss, Dr. Ruth D. Turner, and Ms. Carey Westermann (1877-78) and in the Caribbean Sea (1879-80), by the U.S. (MCZ); the late Dr. Thomas Pulley and Ms. Constance Coast Survey Steamer "Blake," Lieut.-Commander C. D. Boone (HMNS); Mr. Hugh J. Porter (UNC-IMS); Dr. E. Sigsbee, U.S.N., and Commander J. R. Bartlett, U.S.N., de C. Rios (MORG); Mr. William G. Lyons (FSBC I); commanding. XXIX. Report on the Mollusca. Part II. Gas­ and Ms. Amy L. Edwards (LIU, and University of Geor­ tropoda and Scaphopoda. Bulletin of the Museum of Com­ gia, Sapelo Island). We also thank the following for al­ parative Zoology at Harvard College 18:1-492, pis. 1-40. lowing examination of specimens in their personal col­ Dall, W. H. 1895. Diagnosesof new Tertiary fossils from the lections: Gary A. Coovert (Dayton, OH), C. John Finlay southern United States. Proceedings of the United States National Museum 18(1035):21-46. (Palm Bay, FL), James H. Keeler (Tallahassee, FL), Har­ Dall, W. H. 1903a. Contributions to the Tertiary fauna of ry G. Lee (Jacksonville, FL), Colin Redfern (Boca Raton, Florida with especial reference to the SilexBedsof Tampa FL), Peggy Williams (Sarasota, FL), and Jack Worsfold and the Pliocene beds of the Caloosahatchie [sic] River ... (Freeport, Bahamas). P. A. Linley (HBOI) and R. Bieler Part VI. Concluding the work. Transactions of the Wagner [Smithsonian Marine Station at Link Port (SMSLP), Ft. Free Institute of Science of Philadelphia 3:1219-1654, pis. Pierce, FL] read and commented on various versions of 48-60. Page 58 THE NAUTILUS, Vol. 101, No.2

Dall, W. H. 1903b. A preliminary catalogue of the shell­ March, O. A. L. 1875. Synopsis molluscorum marinorum In­ bearing marine mollusks and brachiopods of the south­ diarum occidentalium. Malakozoologische Blatter fur 1874 eastern coast of the United States, with illustrations of und 1875, 22:142-184. many of the species. Reprint, to which are added 21 plates Olsson, A. A. 1922. The Miocene of northern Costa Hica, with not in the edition of 1889. United States National Museum notes on its general stratigraphical relations. Part I. Bul­ Bulletin 37, new edition, 232 p., 95 pIs. letins of American Paleontology 9(39):309 p., 32 pIs. Emmons, E. 1858. Report of the North Carolina Geological Orbigny, A. d'. 1841. Mollusques, vol. 1. In: Sagra, H. Histoire Survey. Agriculture of the eastern counties; together with physique, politique, et naturelle de l'Ile de Cuba. Paris, \ . descriptions of the fossils of the Marl Beds. Bulletins of 264 p. American Paleontology 56(249):230 p. Orbigny, A. d'. 1842. Mollusques, atlas. In: Sagra, R. Histoire Gabb, W. M. 1873. [On the] Topography and geology of Santo physique, politique, et naturelle de l'Ile de Cuba. Paris. .I •I Domingo. Transactions of the American Philosophical So­ Peile, A. J. 1926. The Mollusca of Bermuda. Proceedings of ciety 15:49-259, 2 maps. the Malacological Society of London 17(2-3):71-98. Gabb, W. M. 1881. Descriptions of new species of fossils from Perrilliat, M. d. C. 1974. Monografia de los moluscos del the Pliocene clay beds between Limon and Moen, Costa Mioceno medio de Santa Rosa, Veracruz, Mexico. Parte Rica, together with notes on previously known species from III. Casteropodos: Pyramidellidae a Siphonariidae. Uni­ there and elsewhere in the Caribbean area. Journal of the versidad Nacional Autonoma de Mexico, Instituto de Geo­ Academy of Natural Sciences of Philadelphia 8:349-380. logia, Paleontologia Mexicana No. 37:1-46, pls. 1-8, 1 Gray, J. E. 1847. A list of genera of Recent Mollusca, their table. synonyms and types. Proceedings of the Zoological Society Pilsbry, H. A. 1895. Tectibranchiata. Manual of Conchology of London, Part 15:129-219. 15:181-436, pIs. 43-50, 59-61. Guppy, R. J. L. 1867. Notes on West Indian geology, with Rehder, H. A. 1981. The Audubon Society field guide to North remarks on the existence of an Atlantis in the Early Ter­ American seashells. Alfred A. Knopf, New York, 894 p. tiary period; and descriptions of some new fossils, from Rice, W. H. and L. S. Kornicker. 1965. Mollusks from the the Caribean [sic] Miocene. Geological Magazine 4:496­ deeper waters of the northwestern Campeche Bank, Mex­ 501. ico. Publications of the Institute of Marine Science, Uni­ Guppy, R. J. L. 1876. On the Miocene fossils of Haiti. Quar­ versity of Texas 10:108-172. terly Journal of the Geological Society 32:516-532, pls, 28, Robinson, E. and J. L. Lamb. 1970. Preliminary paleomag­ 29. netic data from the Plio-Pleistocene of Jamaica. Nature Ihering, H. von. 1915. Die Opisthobranchien der brasilian­ 227(5264): 1236-1237. ischen Kiiste. Nachrichtsblatt der Deutschen Malakozoo­ Say, T. 1826. Descriptions of marine shells recently discov­ logischen Gesellschaft 47(3):133-144. ered on the coast of the United States. Journal of the Johnson, C. W. 1934. List of the marine Mollusca of the Academy of Natural Sciences of Philadelphia 5:207-221. Atlantic coast from Labrador to Texas. Proceedings of the Smith, E. A. 1872. Hemarks on several species of Bullidae, Boston Society of Natural History 40(1):1-204. with descriptions of some hitherto undescribed forms, and Knight, J. B. 1952. Primitive fossil gastropods and their bear­ of a new species of Planaxis. Annals and Magazine of ing on gastropod classification. Smithsonian Miscellaneous Natural History 4(9):344-355. Collections 117(13):1-56, pIs. 1,2. Smith, E. A. 1890. Report of the marine molluscan fauna of Lange de Morretes, F. 1949. Ensaio de catalogo dos moluscos the island of St. Helena. Proceedings of the Zoological do Brasil. Arquivos do Museu Paranaense 7(art. 1):5-216. Society of London [April 1, 1890]:247-319, 4 pls, Marcus, E. and E. Marcus. 1964. Verzeichnis der euthyneuren Smith, S. T. 1967. The development of Retusa obtusa (Mon­ Meeresschnecken Brasiliens. Beitriige zur Neotropischen tagu) (, ). Canadian Journal of Fauna 3:195-206. Zoology 45:737-764. Maury, C. J. 1917. Santo Domingo type sections and fossils. Turner, H. D., R. A. Lutz, and D. Jablonski. 1985. Modes of Part I. Bulletins of American Paleontology 5(29):165-415, molluscan larval development at deep-sea hydrothermal 39 pIs. vents. Bulletin of the Biological Society of Washington No. Maury, C. J. 1922. Recent Mollusca of the Gulf of Mexico 6:167-184. and Pleistocene and Pliocene species from the Gulf states. Verrill, A. E. and K. J. Bush. 1900. Additions to the marine Part 2. Scaphopoda, Gastropoda, Amphineura, Cephalop­ Mollusca of the Bermudas. Transactions of the Connecticut oda. Bulletins of American Paleontology 9(38):1-142. Academy of Sciences 10:513-544, pIs. 63-65. Mikkelsen, P. S. 1985. A rapid method for slide mounting of Warmke, G. and H. T. Abbott. 1962. Caribbean seashells. minute radulae, with a bibliography of radula mounting Dover Publications, New York, xx + 348 p., 44 pIs. ( ( techniques. The Nautilus 99(2-3):62-65. Woodring, W. P. 1928. Contributions to the geology and Mikkelsen, P. S. and P. M. Mikkelsen. 1984. Comparison of paleontology of the West Indies. Miocene mollusks from Acteocina canaliculata (Say, 1826), A. candei (d'Orbigny, Bowden, Jamaica. Part II. Gastropods and discussion of 1841) and A. atrata sp. nov. (Gastropoda: ). results. Carnegie Institute of Washington, 564 p., 40 pls, .. .. The Veliger 27(2):164-192.