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Criteria for recognizing marine hermit crabs in the fossil record using gastropod shells

Published online by Cambridge University Press:  20 May 2016

S. E. Walker*
Affiliation:
Department of Paleontology, University of California, Berkeley 94720

Abstract

Hermit crabs have left a rich fossil legacy of epi- and endobionts that bored or encrusted hermit crab-inhabited shells in specific ways. Much of this rich taphonomic record, dating from the middle Jurassic, has been overlooked. Biological criteria to recognize hermitted shells in the fossil record fall within two major categories: 1) massive encrustations, such as encrusting bryozoans; and 2) subtle, thin encrustations, borings, or etchings that surround or penetrate the aperture of the shell. Massive encrustations are localized in occurrence, whereas subtle trace fossils and body fossils are common, cosmopolitan, and stratigraphically long-ranging. Important trace fossils and body fossils associated with hermit crabs are summarized here, with additional new fossil examples from the eastern Gulf Coast. Helicotaphrichnus, a unique hermit crab-associated trace fossil, is reported from the Eocene of Mississippi, extending its stratigraphic range from the Pleistocene of North America and the Miocene of Europe.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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References

Abel, O. 1912. Grundzuge der palaeobiologie der wirbeltiere. E. Schweizerbartsche, Stuttgart, 708 p.Google Scholar
Adegoke, O. S. 1967. Bryozoan–mollusk relationships. The Veliger, 9:298300.Google Scholar
Allman, G. J. 1872. Notice of a fossil hydractinia from the Coralline Crag. Geological Magazine, 9:337338.CrossRefGoogle Scholar
Al-Ogily, S. M., and Knight-Jones, E. W. 1981. Circeis paguri, the spirorbid polychaete associated with the hermit-crab Eupagurus bernhardus. Journal of the Marine Biological Association of the United Kingdom, 61:821826.Google Scholar
Andre, M., and Lamy, E. 1936. Colonies d'hydraires ou de bryozoaires fixees sur des coquilles a pagures. Bulletin Societe Zoologique de France, 61:9499.Google Scholar
Andrews, E. A. 1891. Report on the annelid polychaeta of Beaufort, North Carolina. Proceedings of the United States National Museum, 14:277302.Google Scholar
Baluk, W., and Radwanski, A. 1979. Boring ctenostomate bryozoans from the Korytnica Clays (Middle Miocene; Holy Cross Mountains, Central Poland). Acta Geologica Polonica, 29:243252.Google Scholar
Baluk, W., and Radwanski, A. 1984. New data on the Korytnica Basin, its organic communities and ecological relationships between species (middle Miocene; Holy Cross Mountains, central Poland). Acta Geologica Polonica, 34:179194.Google Scholar
Baluk, W., and Radwanski, A. 1985. Slipper-limpet gastropods (Crepidula) from the Eocene glauconitic sandstone of Kressenberg (Bavarian Alps, West Germany). Neues Jahrbuch fur Geologie und Palaontologie, Monatschefte, 4:237247.Google Scholar
Bassler, R. S. 1953. Bryozoa, p. G1G253. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. G. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Berkeley, E., and Berkeley, C. 1936. Notes on polychaeta from the coast of western Canada 1. Spionidae. Annals and Magazine of Natural History, Series 10, 18:468477.Google Scholar
Berkeley, E., and Berkeley, C. 1956. On a collection of polychaetous annelids from northern Banks Island, from the south Beaufort Sea, and from northwest Alaska: together with some new records from the east coast of Canada. Journal of the Fishery Research Board of Canada, 13:233246.CrossRefGoogle Scholar
Bishop, G. A. 1983. Fossil decapod crustacea from the Late Cretaceous Coon Creek Formation, Union County, Mississippi. Journal of Crustacean Biology, 3:417430.Google Scholar
Blake, J. A. 1969. Reproduction and larval development of Polydora from northern New England (Polychaeta: Spionidae). Ophelia, 7:163.Google Scholar
Blake, J. A. 1971. Revision of the genus Polydora from the east coast of North America (Polychaeta: Spionidae). Smithsonian Contributions to Zoology, 75:132.CrossRefGoogle Scholar
Blake, J. A., and Evans, J. W. 1973. Polydora and related genera: borers in mollusc shells and other calcareous substrates. The Veliger, 1:235249.Google Scholar
Blake, J. A., and Woodwick, K. H. 1972. New species of Polydora (Polychaeta: Spionidae) from the coast of California. Bulletin Southern California Academy of Science, 70:7279.Google Scholar
Boekschoten, G. J. 1966. Shell borings of sessile epibiontic organisms as palaeoecological guides (with examples from the Dutch coast). Palaeogeography, Palaeoclimatology, Palaeoecology, 2:333379.Google Scholar
Boekschoten, G. J. 1967. Paleoecology of some mollusca from the Tielrode Sands (Pliocene, Belgium). Palaeogeography, Palaeoclimatology, Palaeoecology, 3:311362.CrossRefGoogle Scholar
Bottjer, D. 1981. Periostracum of the gastropod Fusitriton oregonensis: natural inhibitor of boring and encrusting organisms. Bulletin of Marine Science, 31:916921.Google Scholar
Buge, E., and Fischer, J-C. 1970. Atractosoecia incrustans (d'Orbigny) (Bryozoa Cyclostomata) espece Bathonienne symbiotique d'un pagure. Bulletin Societe Zoologique de France, (7) 1:126133.Google Scholar
Buge, E., and Lecointre, G. 1962. Une association biologique (symbiose) entre un bryozoaire et un pagure dans le Quaternaire du Rio de Oro (Sahara Espagnol). Bulletin Societe Geologique de France, (7) 4:555558.Google Scholar
Buss, L. W., and Yund, P. O. 1988. A comparison of modern and historical populations of the colonial hydroid Hydractinia. Ecology, 69:646654.Google Scholar
Buss, L. W., and Yund, P. O. 1989. A sibling species group of Hydractinia in the northeastern United States. Journal of the Marine Biological Association of the United Kingdom, 69:857874.CrossRefGoogle Scholar
Cairns, S. D., and Barnard, J. L. 1984. Redescription of Janaria mirabilis, a calcified hydroid from the Eastern Pacific. Bulletin Southern California Academy of Science, 83:111.Google Scholar
Carlton, J. T. 1971. Gastropod shell modifications by hermit crabs, and paleoecological implications. Abstracts and Proceedings of the Western Society of Malacologists, 5:23.Google Scholar
Carlton, J. T., and Roth, B. 1975. Phylum Mollusca: shelled gastropods, p. 467514. In Smith, R. I. and Carlson, J. T. (eds.), Light's Manual: Intertidal Invertebrates of the Central California Coast. University of California Press, Berkeley.Google Scholar
Carter, H. J. 1877. On the close relationship of Hydractinia, Parkeria, and Stromatopora; with descriptions of new species of the former, both Recent and fossil. Annals and Magazine of Natural History, Series 4, 19:4475.Google Scholar
Carter, H. J. 1882. Remarkable forms of Cellepora and Polythoa from Senegambian Coast. Annals and Magazine of Natural History, Series 5, 11:416419.CrossRefGoogle Scholar
Conover, M. R. 1975. Prevention of shell burial as a benefit hermit crabs provide their symbionts (Decapoda, Paguridea). Crustaceana, 29:311313.CrossRefGoogle Scholar
Conover, M. R. 1976. The influence of some shell symbionts on the shell selection behavior of the hermit crabs, Pagurus pollicaris and Pagurus longicarpus. Animal Behavior, 25:191194.Google Scholar
Conover, M. R. 1978. The importance of various shell characters to the shell-selection behavior of hermit crabs. Journal of Experimental Marine Biology and Ecology, 32:131142.CrossRefGoogle Scholar
Conover, M. R. 1979. Effect of gastropod shell characteristics and hermit crabs on shell epifauna. Journal of Experimental Marine Biology and Ecology, 40:8194.Google Scholar
Cook, P. L. 1964. Polyzoa from West Africa. Notes on the genera Hippoporina Neviani, Hippoporella Canu, Cleidochasma Harmer and Hippoporidra Canu and Bassler (Cheilostomata, Ascophora). Bulletin British Museum of Natural History, London (Zoology), 12:135.Google Scholar
Cook, P. L. 1968. Observations on living bryozoa. Atti Societa Italiana di Scienze Naturali Museo Civico di Storia Naturale di Milano, 108:155160.Google Scholar
Darrell, J. G., and Taylor, P. D. 1989. Scleractinian symbionts of hermit crabs in the Pliocene of Florida. Memoir of the Association of Australasian Palaeontologists, 8:115123.Google Scholar
Darwin, C. 1854. A monograph on the sub-class Cirripedia (the Balanidae, the Verrucidae). Volume 2. The Ray Society, London, 684 p.Google Scholar
Deichmann, E. 1954. The “Texas longhorn shells” from the Florida waters. Nautilus, 67:7680.Google Scholar
Ehrenberg, K. 1931. Uber lebensspuren von einsiedlerkrebsen. Palaeobiologica, 4:137174.Google Scholar
Foster, N. M. 1971. Spionidae (Polychaeta) of the Gulf of Mexico and the Caribbean Sea. Studies on the fauna of Curacao and other Caribbean Islands, 36:1183.Google Scholar
Fotheringham, N. 1976. Population consequences of shell utilization by hermit crabs. Ecology, 57:570578.Google Scholar
Fraas, E. 1911. Eine rezente Kerunia-bildung. Verhandlungen Zoologisch-Botanische Gesellschaft in Wien, 61:7077.Google Scholar
Frey, R. W. 1987. Hermit crabs: neglected factors in taphonomy and paleoecology. Palaios, 2:313322.CrossRefGoogle Scholar
Glaessner, M. 1969. Decapoda, p. R399R566. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. R, Arthropoda 4. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Gordon, D. P. 1972. Biological relationships of an intertidal bryozoan population. Journal of Natural History, 6:503514.Google Scholar
Gyllenhaal, E., and Kidwell, S. M. 1989. Growth histories of sub-spherical bryozoan colonies: Ordovician and Pliocene evidence for paleocurrent regimes and commensalism. Geological Society of America, Abstracts with Programs, 21:A112A113.Google Scholar
Hancock, A. 1849. Notice of the occurrence on the British coast of a burrowing barnacle belonging to a new order of class cirripedia. Annals and Magazine of Natural History, Series 2, 4:305314.Google Scholar
Häntzschel, W. 1975. Trace fossils and problematica, p. R400R651. In Teichert, C. (ed.), Treatise on Invertebrate Paleontology, Pt. 4(2), Arthropoda. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Hartman, O. 1941. Polychaetous annelids. Part 3. Spionidae. Some contributions to the biology and life history of Spionidae from California. Allan Hancock Pacific Expedition, 7:289323.Google Scholar
Hatfield, P. A. 1965. Polydora commensalis Andrews—Larval development and observations on adults. Biological Bulletin, 128:356368.Google Scholar
Hendler, G., and Franz, D. R. 1971. Population dynamics and life history of Crepidula convexa Say (Gastropoda: Prosobranchia) in Delaware Bay. Biological Bulletin, 141:514526.Google Scholar
Hill, S. D., and Wells, J. W. 1956. Hydroida and Spongiomorphida, p. F81F89. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, Pt. F, Coelenterata. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Hoagland, K. E. 1977. Systematic review of fossil and recent Crepidula and discussion of evolution of the Calyptraeidae. Malacologia, 16:353420.Google Scholar
Hyden, F. M., and Forest, J. 1980. An in situ hermit crab from the early Miocene of southern New Zealand. Palaeontology, 23:471474.Google Scholar
Jensen, K., and Bender, K. 1973. Invertebrates associated with snail shells inhabited by Pagurus barnhardus (L.) (Decapoda). Ophelia, 10:185192.Google Scholar
Jones, H. D. 1984. Shell cleaning behaviour of Calliostoma zizyphinum. The Journal of Molluscan Studies, 50:245247.Google Scholar
Karlson, R. H., and Cariolou, M. A. 1982. Hermit crab shell colonization by Crepidula convexa Say. Journal of Experimental Marine Biology and Ecology, 65:110.CrossRefGoogle Scholar
Karlson, R. H., and Shenk, M. A. 1983. Epifaunal abundance, association, and overgrowth patterns on large hermit crab shells. Journal of Experimental Marine Biology and Ecology, 70:5564.Google Scholar
Kern, J. P. 1979. The ichnofossil Helicotaphrichnus commensalis in the Korytnica basin (Middle Miocene; Holycross Mountains, central Poland). Acta Geologica Polonica, 29:239242.Google Scholar
Kern, J. P., Grimmer, J. C., and Lister, K. H. 1974. A new fossil spionid tube, Pliocene and Pleistocene of California and Baja California. Journal of Paleontology, 48:978982.Google Scholar
Kirkpatrick, R., and Metzelaar, J. 1922. On an instance of commensalism between a hermit crab and a polyzoan. Proceedings of the Zoological Society of London, Pt. 4:983990.Google Scholar
Lecointre, G. 1929. Symbiose des cellepores et des gastropodes dans les faluns de Touraine. Bulletin Societe Geologique de France, 29:401404.Google Scholar
MacNeil, F. S., and Dockery, D. T. III. 1984. Lower Oligocene Gastropoda, Scaphopoda, and Cephalopoda of the Vicksburg Group in Mississippi. Mississippi Department of Natural Resources Bureau of Geology, Bulletin 124:1389.Google Scholar
Mayer-Eymar, C. 1900. Un singulier cephalopode de l'Eocene d'Egypte, qu'il nomme Kerunia cornuta. Ecologae Geologicae Helvetiae, 6:120121.Google Scholar
McKinney, F. K., and Jackson, J. B. C. 1989. Bryozoan Evolution. Unwin Hyman, Boston, 238 p.Google Scholar
McLean, R. 1983. Gastropod shells: a dynamic resource that helps shape benthic community structure. Journal of Experimental Marine Biology and Ecology, 6:151174.Google Scholar
Merrill, A. S. 1967a. Shell deformity of mollusks attributable to the hydroid, Hydractinia echinata. Fishery Bulletin, 66:273279.Google Scholar
Merrill, A. S. 1967b. Offshore distribution of Hydractinia echinata. Fishery Bulletin, 66:281283.Google Scholar
Miller, W. III, and Brown, N. 1979. The attachment scars of fossil balanids. Journal of Paleontology, 53:208210.Google Scholar
Mills, C. 1976. The association of hydractiniid hydroids and hermit crabs, with new observations from North Florida, p. 467476. In Mackie, G. O. (ed.), Coelenterate Ecology and Behavior. Plenum Press, New York.Google Scholar
Moore, E. 1963. Miocene marine mollusks from the Astoria Formation in Oregon. U.S. Geological Survey Professional Paper, 419:1109.Google Scholar
Morris, R. H., Abbott, D. P., and Haderlie, E. C. 1980. Intertidal Invertebrates of California. Stanford University Press, Stanford, 690 p.Google Scholar
Palmer, T. J. 1972. Ectoproct/gastropod and ectoproct/pagurid symbiosis from the Upper Bathonian of Calvados, France. Palaeontological Association Circular, 72:10.Google Scholar
Palmer, T. J., and Hancock, C. D. 1973. Symbiotic relationships between ectoprocts and gastropods, and ectoprocts and hermit crabs in the French Jurassic. Palaeontology, 16:563566.Google Scholar
Petuch, E. J. 1986. The Pliocene reefs of Miami: their geomorphological significance in the evolution of the Atlantic coastal Ridge, southeastern Florida. Journal of Coastal Research, 2:391408.Google Scholar
Pinter Morris, P. A. 1974. A comparative study of decalcification of mollusc shells by various bryozoans, p. 109113. In Bryozoa 1974. Documents des Laboratoires de Geologie de la Faculte des Sciences de Lyon, 3 (fasc. 1).Google Scholar
Pohowsky, R. A. 1978. The boring ctenostomate bryozoa: taxonomy and paleobiology based on cavities in calcareous substrata. Bulletin of American Paleontology, 73:1192.Google Scholar
Radwanski, A. 1977. Present-day types of traces in the Neogene sequence: their problems of nomenclature and preservation, p. 227264. In Crimes, T. P. and Harper, J. C. (eds.), Trace Fossils, Volume 2. Seel House Press, Liverpool, London.Google Scholar
Rice, M. E. 1976. Sipunculans associated with coral communities. Micronesica, 12:119132.Google Scholar
Samuelson, T. J. 1970. The biology of six species of Anomura (Crustacea: Decapoda) from Raunefjorden, western Norway. Sarsia, 45:2552.CrossRefGoogle Scholar
Schafer, W. 1972. Ecology and Paleoecology of Marine Environments. The University of Chicago Press, Chicago, 624 p.Google Scholar
Schembri, P. J. 1982. Feeding behavior of 15 species of hermit crabs (Crustacea: Decapoda: Anomura) from the Otago Region, Southeastern New Zealand. Journal of Natural History, 16:859878.Google Scholar
Scully, E. P. 1979. The effects of gastropod shell availability and habitat characteristics on shell utilization by the intertidal hermit crab Pagurus longicarpus Say. Journal of Experimental Marine Biology and Ecology, 37:139152.CrossRefGoogle Scholar
Seilacher, A. 1969. Paleoecology of boring barnacles. American Zoologist, 9:705719.Google Scholar
Shimoyama, S. 1979. Modification of shell distribution patterns by hermit crabs in a protected shore. Marine Science, 11:527535.Google Scholar
Shimoyama, S. 1985. Size-frequency distribution of living populations and dead shell assemblages in a marine intertidal sand snail, Umbonium (Suchium) moniliferum (Lamarck), and their palaeoecological significance. Palaeogeography, Palaeoclimatology, Palaeoecology, 49:327353.Google Scholar
Shimoyama, S., Yosida, T., and Shuto, T. 1979. Modification of palaeontological information caused by selective utilization of empty shells by an intertidal hermit crab, Diogenes edwardsi (Detaan). Report Fishery Research Laboratory Kyushu University, 4:6578.Google Scholar
Silen, L. 1947. On the anatomy and biology of Penetrantiidae and Immergentiidae (Bryozoa). Arkiv foer Zoologi, (Stockholm), 40A(3):148.Google Scholar
Smith, A. G. 1966. Staghorns and longhorns. Pacific Discovery, 19:3031.Google Scholar
Spight, T. M. 1977. Availability and use of shells by intertidal hermit crabs. Biological Bulletin, 152:120133.Google Scholar
Stachowitsch, M. 1977. The hermit crab microbiocoenosis—the role of mobile secondary hard bottom elements in a North Adriatic benthic community, p. 549558. In Keegan, B. F., Ceidigh, P. O., and Boaden, P. J. (eds.), Biology of Benthic Organisms. Proceedings of the European Marine Biological Symposium. Pergamon, London.Google Scholar
Stachowitsch, M. 1979. Movement, activity pattern, and role of a hermit crab population in a sublittoral epifauna community. Journal of Experimental Marine Biology and Ecology, 39:135150.Google Scholar
Stachowitsch, M. 1980. The epibiotic and endolithic species associated with the gastropod shells inhabited by the hermit crabs Paguristes oculatus and Pagurus cuanensis. Marine Ecology Pubblicazioni della Stazione Zoologica di Napoli, 1:73104.Google Scholar
Taylor, P. D. 1981. Associations between bryozoans and hermit crabs. Abstracts of the Palaeontological Association Annual Conference, University of Exeter, p. 12.Google Scholar
Taylor, P. D., and Cook, P. L. 1981. Hippoporidra edax (Busk, 1859) and a revision of some fossil and living Hippoporidra (Bryozoa). Bulletin British Museum of Natural History (Geology), 35:243251.Google Scholar
Taylor, P. D., Schembri, P. J., and Cook, P. L. 1989. Symbiotic associations between hermit crabs and bryozoans from the Otago region, southeastern New Zealand. Journal of Natural History, 23:10591085.Google Scholar
Tomlinson, J. T. 1955. The morphology of an acrothoracican barnacle Trypetresa lateralis. Journal of Morphology, 96:97114.Google Scholar
Tomlinson, J. T. 1969a. Shell-burrowing barnacles. American Zoologist, 9:837840.Google Scholar
Tomlinson, J. T. 1969b. The burrowing barnacles (Cirripedia: order Acrothoracica). Smithsonian Institution, United States National Museum Bulletin, 296:1162.Google Scholar
Tomlinson, J. T. 1987. The burrowing barnacles (Acrothoracica), p. 6371. In Southward, A. J. (ed.), Barnacle Biology. A. A. Balkema, Rotterdam.Google Scholar
Turquier, Y. 1967. Description d'un nouveau Trypetesa Norman (Alcippe Hancock), Cirripede Acrothoracique des cotes francaises de la Manche. Cahiers de Biologie Marine, VIII:7587.Google Scholar
Ulrich, E. O. 1904. Hydrozoa. Maryland Geological Survey, 2(1):433447.Google Scholar
Utinomi, H. 1962. Occurrence of a Trypetesa in Japan. Zoological Magazine (Tokyo), 71:399.Google Scholar
Vance, R. R. 1972. Competition and mechanisms of coexistence in three sympatric species of intertidal hermit crabs. Ecology, 53:10621074.Google Scholar
Vermeij, G. J. 1978. Biogeography and Adaptation: Patterns of Marine Life. Harvard University Press, Cambridge, 332 p.Google Scholar
Vermeij, G. J. 1987. Evolution and Escalation, an Ecological History of Life. Princeton University Press, New Jersey, 527 p.Google Scholar
Vermeij, G. J., Lowell, R. B., Walters, L. J., and Marks, J. A. 1987. Good hosts and their guests: relations between trochid gastropods and the epizoic limpet Crepidula adunca. The Nautilus, 101:6974.Google Scholar
Walker, S. E. 1985. Shell fouling organisms of Olivella biplicata (Sowerby, 1825) and hermit crab behavior. Western Society of Malacologists Annual Report, 18:2930.Google Scholar
Walker, S. E. 1986. The influence of hermit crabs on gastropod taphonomy. Fourth North American Paleontological Convention, University of Colorado, Boulder, p. A48.Google Scholar
Walker, S. E. 1988a. Hermit crabs and their influence on gastropod taphonomy. Unpubl. Ph.D. dissertation, University of California, Berkeley, 267 p.Google Scholar
Walker, S. E. 1988b. Taphonomic significance of hermit crabs (Anomura: Paguridea): epifaunal hermit crab-infaunal gastropod example. Palaeogeography, Palaeoclimatology, Palaeoecology, 63:4571.Google Scholar
Walker, S. E. 1989. Hermit crabs as taphonomic agents. Palaios, 4:439452.Google Scholar
Walker, S. E. 1990. Biological taphonomy and gastropod temporal dynamics. The Paleontological Society Special Publication, No. 5:391421.Google Scholar
Walker, S. E. 1991. Taphonomy and paleoecology of Villamil fossil megagastropods of Isla Isabela, p. 423437. In James, M. (ed.), Galapagos Marine Invertebrates: Taxonomy, Biogeography, and Evolution in Darwin's Islands. Plenum Press, New York.Google Scholar
Walker, S. E., and Yamada, S. B. 1990. Mistaken crab predation on empty snail shells. Western Society of Naturalists, p. 64.Google Scholar
Weisbord, N. E. 1974. Late Cenozoic corals of South Florida. Bulletins of American Paleontology, 66:255544.Google Scholar
White, F. 1969. Distribution of Trypetesa lampas (Cirripedia, Acrothoracica) in various gastropod shells. Marine Biology, 4:333339.Google Scholar
Woodring, W. 1956. Geology and paleontology of Canal zone and adjoining parts of Panama. Geology and description of Tertiary mollusks (Gastropods: Trochidae to Turritellidae). U.S. Geology Survey Professional Paper, 306-A:1146.Google Scholar
Woodring, W., Bramlett, M., and Kew, W. 1946. Geology and paleontology of Palos Verdes Hills, California. U.S. Geological Survey Professional Paper, 15:114.Google Scholar
Woodwick, K. H. 1963. Taxonomic revision of two polydorid species. Proceedings of the Biological Society of Washington, 76:209216.Google Scholar
Yund, P. O., Cunningham, C. W., and Buss, L. 1987. Recruitment and post-recruitment interactions in a colonial hydroid. Ecology, 68:971982.Google Scholar
Yund, P. O., and Parker, H. M. 1989. Population structure of the colonial hydroid Hydractinia sp. nov. C in the Gulf of Maine. Journal of Experimental Marine Biology and Ecology, 125:6382.Google Scholar
Zapfe, H. 1936. Spuren bohrender cirripedier in gastropoden-gehausen des Miozans. Senckenbergiana, 18:130134.Google Scholar
Zapfe, H. 1947. Spuren von paguriden an tertiaren gastropodengehausen, p. 289298. In Papp, A., Zapfe, H., Bachmayer, F., and Tauber, A., Lebensspuren mariner krebse. Akademie der Wissenschaften, Wien, Mathematisch Naturwissenschaftliche Klasse, Sitzungsberichte, Abteilung 1, 155.Google Scholar