Comparative morphology of the body wall in flatworms (Platyhelminthes)

Canadian Journal of Zoology

Volumn 82, Issue 2, 2004, Pages 194-210

  Tyler, Seth ^a   Hooge, Matthew ^a  

^a UNIVERSITY OF MAINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BIOLOGICAL MEMBRANES; CELLS; MUSCLE;

BODY WALL; PLATYHELMINTHS;

MICROORGANISMS;

ECOMORPHOLOGY; FLATWORM; PARASITE; ULTRASTRUCTURE;

ACOELA; CATENULIDA; NEODERMATA; PLATYHELMINTHES; TURBELLARIA; TYPHLOPLANOIDA;

EID: 3142680442     PISSN: 00084301     EISSN: None     Source Type: Journal    
DOI: 10.1139/z03-222     Document Type: Review

References (136)

1. An der Lan, H. 1936. Ergebnisse einer von E. Reisinger und O. Steinböck mit Hilfe des Rask-Orested Fonds durchgeführten Reise in Grönland 1926. 7. Acoela I. Vidensk. Medd. Dan. Nathist. Foren. 99: 289-329.
2. Baguñà, J. 1981. Planarian neoblasts. Nature (Lond.), 290: 14-15.
3. Baguñà, J., and Boyer, B.C. 1990. Descriptive and experimental embryology of the Turbellaria: present knowledge, open questions and future trends. In Experimental embryology in aquatic plants and animals. Edited by H.-J. Marthy. Plenum Press, New York. pp. 95-128.
4. Baguñà, J., Salo, E., and Auladell, C. 1989. Regeneration and pattern formation in planarians III. Evidence that neoblasts are totipotent stem cells and the source of blastema cells. Development (Camb.), 107: 77-86.
5. Baguñà, J., Salo, E., Romero, R., and Garcia-Fernandez, J. 1994. Regeneration and pattern formation in planarians: cells, molecules and genes. Zool. Sci. (Tokyo), 11: 781-795.
6. Bedini, C., and Papi, F. 1974. Fine structure of the turbellarian epidermis. In Biology of the Turbellaria. Edited by N.W. Riser and M.P. Morse. McGraw-Hill, New York. pp. 108-147.
7. Benazzi, M., and Gremigni, V. 1982. Developmental biology of triclad turbellarians (Planaria). In Developmental biology of freshwater invertebrates. Edited by F.W. Harrison and R.R. Cowden. Alan R. Liss, New York. pp. 151-211.
8. Borkott, H. 1970. Geschlechtliche Organisation, Fortpflanzungsverhalten und Ursachen der sexuellen Vermehrung von Stenostomum sthenum nov. spec. (Turbellaria, Catenulida). Z. Morphol. Tiere, 67: 183-262.
9. Boyer, B.C., Henry, J.J., and Martindale, M.Q. 1996. Dual origins of mesoderm in a basal spiralian: cell lineage analyses in the polyclad turbellarian Hoploplana inguilina. Dev. Biol. 179: 329-338.
10. Boyer, B.C., Henry, J.J., and Martindale, M.Q. 1998. The cell lineage of a polyclad turbellarian embryo reveals close similarity to coelomate spiralians. Dev. Biol. 204: 111-123.
11. Bresciani, J., and Koie, M. 1970. On the ultrastructure of the epidermis of the adult female of Kronborgia amphipodicola Christensen & Kanneworff, 1964 (Turbellaria, Neorhabdocoela). Ophelia No. 8. pp. 209-230.
12. Bresslau, E. 1928-1933. Turbellaria. In Handbuch der Zoologie. Vol. II, Part I. Edited by W. Kükenthal and T. Krumbach. Walter de Gruyter, Berlin. pp. 52-304.
13. Cannon, L.R.G., and Joffe, B.I. 2001. The Temnocephalida. In Interrelationships of the Platyhelminthes. Edited by D.T.J. Littlewood and R.A. Bray. Taylor and Francis, London. pp. 83-91.
14. Cebrià, F., and Romero, R. 2001. Body-wall muscle restoration dynamics are different in dorsal and ventral blastemas during planarian anterior regeneration. Belg. J. Zool. 131(Suppl. 1): 111-115.
15. Cebrià, F., Vispo, M., Newmark, P., Bueno, D., and Romero, R. 1997. Myocyte differentiation and body wall muscle regeneration in the planarian Girardia tigrina. Dev. Genes Evol. 207: 306-316.
16. Chien, P.K., and Koopowitz, H. 1977. Ultrastructure of nerve plexus in flatworms. III. The infra-epithelial nervous system. Cell Tissue Res. 176: 335-347.
17. Coil, W.H. 1991. Platyhelminthes: Cestoidea. In Microscopic anatomy of the invertebrates. Vol. 3. Platyhelminthes and Nemertinea. Edited by F.W. Harrison and B.J. Bogitsh. Wiley-Liss Inc., New York. pp. 211-283.
18. Curtis, S.K., Cowden, R.R., Moore, J.D., and Robertson, J.L. 1983. Histochemical and ultrastructural features of the epidermis of the land planarian Bipalium adventitium. J. Morphol. 175: 171-194.
19. De Vocht, A.J.-P., and Schockaert, E. 1999. The anatomy and ultrastructure of the proboscis in Zonorhynchus-species and implications for phylogenetic relationships within the Eukalyptorhynchia Meixner, 1928 (Platyhelminthes, Rhabdocoela). Belg. J. Zool. 129: 219-234.
20. Doe, D.A. 1976. The proboscis hooks in Karkinorhynchidae and Gnathorhynchidae (Turbellaria, Kalyptorhynchia) as basement membrane or intracellular specializations. Zool. Scr. 5: 105-115.
21. Doe, D.A. 1981. Comparative ultrastructure of the pharynx simplex in Turbellaria. Zoomorphology (Berl.), 97: 133-193.
22. Drobysheva, I.M. 1988. An autoradiographic study of the replacement of epidermis in polyclad turbellarians. Fortschr. Zool. 36: 97-102.
23. Ehlers, B. 1977. "Trematoden-artige" Epidermisstrukturen bei einem freilebenden proseriaten Struedelwurm. Acta Zool. Fenn. 154: 129-136.
24. Ehlers, U. 1985. Das Phylogenetische System der Plathelminthes. Gustav Fischer, Stuttgart, Germany.
25. Ehlers, U. 1992a. On the fine structure of Paratomella rubra Rieger & Ott (Acoela) and the position of the taxon Paratomella Dörjes in a phylogenetic system of the Acoelomorpha (Plathelminthes). Microfauna Mar. 7: 265-293.
26. Ehlers, U. 1992b. No mitosis of differentiated epidermal cells in the Plathelminthes: mitosis of intraepidermal stem cells in Rhynchoscolex simplex Leidy, 1851 (Catenulida). Microfauna Mar. 7: 311-321.
27. Ehlers, U. 1994. Ultrastructure of the unusual body wall musculature of Anaperus tvaerminnensis (Plathelminthes, Acoela). Microfauna Mar. 9: 291-300.
28. Erber, A., Riemer, D., Hofemeister, H., Bovenschulte, M.N., Stick, R., Panopoulou, G. et al. 1999. Characterization of the Hydra lamin and its gene: a molecular phylogeny of metazoan lamins. J. Mol. Evol. 49: 260-271.
29. Fredericksen, D.W. 1978. The fine structure and phylogenetic position of the cotylocidium larva of Cotylogaster occidentalis Nickerson 1902 (Trematoda: Aspidogastridae). J. Parasitol. 64: 961-976.
30. Fried, B., and Haseeb, M.A. 1991. Platyhelminthes: Aspidogastrea, Monogenea, and Digenea. In Microscopic anatomy of the invertebrates. Vol. 3: Platyhelminthes and Nemertinea. Edited by F.W. Harrison and B.J. Bogitsh. Wiley-Liss, New York. pp. 141-209.
31. Galliot, B., and Schmid, V. 2002. Cnidarians as a model system for understanding evolution and regeneration. Int. J. Dev. Biol. 46: 39-48.
32. Giesa, S. 1966. Die Embryonalentwicklung von Monocelis fusca (Oersted) (Turbellaria: Proseriata). Z. Morphol. Oekol. Tiere, 57: 137-230.
33. Gschwentner, R., Ladurner, P., Nimeth, K., and Rieger, R. 2001. Stem cells in a basal bilaterian: S-phase and mitotic cells in Convolutriloba longifissura (Acoela, Platyhelminthes). Cell Tissue Res. 304: 401-408.
34. Gschwentner, R., Müller, J., Ladurner, P., Rieger, R., and Tyler, S. 2003. Unique patterns of longitudinal body-wall musculature in the Acoela: the ventral musculature of Convolutriloba longifissura. Zoomorphology (Berl.), 122: 87-94.
35. Hartenstein, V., and Ehlers, U. 2000. The embryonic development of the rhabdocoel flatworm Mesostoma lingua (Abildgaard, 1789). Dev. Genes Evol. 210: 399-415.
36. Haszprunar, G. 1996. Plathelminthes and Plathelminthomorpha - paraphyletic taxa. J. Zool. Syst. Evol. Res. 34: 41-48.
37. Hein, C. 1928. Zur Kenntnis der Regenerationsvorgaenge bei der Rhabdocoelen. Mit Angeben ueber den feineren Bau und die Lebensaeusserungen. Z. Wiss. Zool. 130: 469-546.
38. Henry, J.Q., Martindale, M.Q., and Boyer, B.C. 2000. The unique developmental program of the acoel flatworm, Neochildia fusca. Dev. Biol. 220: 285-295.
39. Hooge, M.D. 2001. Evolution of body-wall musculature in the Platyhelminthes (Acoelomorpha, Catenulida, Rhabditophora). J. Morphol. 249: 171-194.
40. Hooge, M.D., and Tyler, S. 1999: Musculature of the facultative parasite Urastoma cyprinae (Platyhelminthes). J. Morphol. 241: 207-216.
41. Hooge, M.D., and Tyler, S. 2003. Two new acoels (Acoela, Platyhelminthes) from the central coast of California. Zootaxa, 131: 1-14.
42. Hori, I. 1978. Possible role of rhabdite-forming cells in cellular succession of the planarian epidermis. J. Electron Microsc. 27: 89-102.
43. Hori, I. 1989. Observations on planarian epithelization after wounding. J. Submicrosc. Cytol. Pathol. 21: 307-315.
44. Hori, I. 1997. Cytological approach to morphogenesis in the planarian blastema. II. The effect of neuropeptides. J. Submicrosc. Cytol. Pathol. 29: 91-97.
45. Hyman, L.H. 1951. The invertebrates. II. Platyhelminthes and Rhynchocoela. The acoelomate Bilateria. McGraw-Hill, New York.
46. Hyra, G.S. 1993. Genostoma kozloffi sp. nov., and G. inopinatum sp. nov. (Turbellaria: Neorhabdocoela: Genostomatidae) from leptostracan crustaceans of the genus Nebalia. Cah. Biol. Mar. 34: 111-126.
47. Jennings, J.B., Cannon, L.R.G., and Hick, A.J. 1992. The nature and origin of the epidermal scales of Notodactylus handschinian unusual temnocephalid turbellarian ectosymbiotic on crayfish from northern Queensland. Biol. Bull. (Woods Hole), 182: 117-128.
48. Joffe, B.I., and Cannon, L.R.G. 1998. The organization and evolution of the mosaic of the epidermal syncytia in the Temnocephalida (Platyhelminthes: Neoophora). Zool. Anz. 237: 1-14.
49. Jondelius, U. 1988. Epidermal ultrastructure of adults and juveniles of Triloborhynchus astropectinis (Dalyellioida, Platyhelminthes). Fortschr. Zool. 36: 39-44.
50. Jondelius, U. 1989. Pterastericola pellucida n. sp., an endosymbiotic flatworm (Dalyelloida: Pterastericolidae) from Astropecten irregularis with notes on the monophyly of the genus Pterastericola. Ophelia No. 30. pp. 55-62.
51. Jondelius, U., Ruiz-Trillo, I., Baguñà, J., and Riutort, M. 2002. The Nemertodermatida are basal bilaterians and not members of the Platyhelminthes. Zool. Scr. 31: 201-215.
52. Karling, T.G. 1965. Haplopharynx rostratus Meixner (Turbellaria) mit den Nemertinen vergleichen. Z. Zool. Syst. Evolutionsforsch. 3: 1-18.
53. Karling, T.G., and Nilsson, A.M. 1974. Further studies on the genus Hypoblepharina Boehmig (Turbellaria, Dalyellioida), with description of H. serrifera sp. n. Zool. Scr. 3: 59-63.
54. Koie, M., and Bresciani, J. 1973. On the ultrastructure of the larva of Kronborgia amphipodicola Christensen and Kanneworff, 1964 (Turbellaria, Neorhabdocoela). Ophelia No. 12. pp. 171-203.
55. Kotikova, E.A., Raikova, O.I., Reuter, M., and Gustafsson, M.K.S. 2002. The nervous and muscular systems in the free-living flatworm Castrella truncata (Rhabdocoela): an immunocytochemical and phalloidin fluorescence study. Tissue Cell, 34: 365-374.
56. Lacalli, T.C. 1982. The nervous system and ciliary band of Müller's larva. Proc. R. Soc. Lond. B Biol. Sci. 217: 37-58.
57. Ladurner, P., and Rieger, R. 2000. Embryonic muscle development of Convoluta pulchra (Turbellaria-Acoelomorpha, Platyhelminthes). Dev. Biol. 222: 359-375.
58. Ladurner, P., Mair, G., Reiter, D., Salvenmoser, W., and Rieger, R.M. 1997. The serotoninergic nervous system of two macrostomid species: Recent or ancient divergence? Invertebr. Biol. 116: 178-191.
59. Ladurner, P., Rieger, R., and Baguñà, J. 2000. Spatial distribution and differentiation potential of stem cells in hatchlings and adults in the marine platyhelminth Macrostomum sp.: a Bromodeoxyuridine analysis. Dev. Biol. 226: 231-241.
60. Lumsden, R.D., Oaks, J.A., and Mueller, J.F. 1974. Brush border development in the tegument of the tapeworm, Spirometra mansonoides. J. Parasitol. 60: 209-226.
61. Lundin, K. 1997. Comparative ultrastructure of the epidermal ciliary rootlets and associated structures in species of the Nemertodermatida and Acoela (Plathelminthes). Zoomorphology (Berl.), 117: 81-92.
62. Lundin, K. 2001. Degenerating epidermal cells in Xenoturbella (phylum uncertain), Nemertodermatida and Acoela (Platyhelminthes). Belg. J. Zool. 131(Suppl. 1): 153-157.
63. Luther, A. 1904. Die Eumesostominen. Z. Wiss. Zool. 77: 1-273.
64. Luther, A. 1943. Untersuchungen an rhabdocoelen Turbellarien. IV. Über einige Repräsentanten der Familie Proxenetidae. Acta Zool. Fenn. 38: 3-100.
65. Luther, A. 1955. Die Dalyelliiden (Turbellaria Neorhabdocoela), eine Monographie. Acta Zool. Fenn. 87: 1-337.
66. Lyons, K.M. 1973. Epidermal fine structure and development in the oncomiracidium larva of Entobdella soleae (Monogenea). Parasitology, 66: 321-333.
67. Mair, G.R., Maule, A.G., Shaw, C., Johnston, D.F., and Halton, D.W. 1998. Gross anatomy of the muscle systems of Fasciola hepatica as visualized by phalloidin-fluorescence and confocal microscopy. Parasitology, 117: 75-82.
68. Mair, G.R., Maule, A.G., Fried, B., Day, T.A., and Halton, D.W. 2003. Organization of the musculature of schistosome cercariae. J. Parasitol. 89(3): 623-625.
69. McGee, C., Fairweather, I., and Blackshaw, R.P. 1996. Ultrastructural observations on rhabdite formation in the planarian, Artioposthia triangulata. J. Zool. 240: 563-572.
70. McGee, C., Fairweather, I., and Blackshaw, R.P. 1997. Ultrastructural features of the epidermis of the planarian Artioposthia triangulata (Dendy). Hydrobiologia, 347: 15-24.
71. Moraczewski, J. 1977. Asexual reproduction and regeneration of Catenula (Turbellaria, Archoophora). Zoomorphologie, 88: 65-80.
72. Newmark, P.A., and Sánchez Alvarado, A. 2002. Not your father's planarian: a classic model enters the era of functional genomics. Nat. Rev. Genet. 3: 210-220.
73. Noldt, U. 1988. Serratorhynchus stellatus, a new schizorhynchid species (Plathelminthes) with sawblade-like proboscis hard structures. Fortschr. Zool. 36: 385-390.
74. Orii, H., Ito, H., and Watanabe, K. 2002. Anatomy of the planarian Dugesia japonica. I. The muscular system revealed by antisera against myosin heavy chains. Zool. Sci. (Tokyo), 19: 1123-1131.
75. Ott, J., Rieger, G., Rieger, R., and Enders, F. 1982. New mouthless interstitial worms from the sulfide system: symbiosis with prokaryotes. Mar. Ecol. 3: 313-333.
76. Palladini, G., Medolago-Albani, L., Margotta Conforti, A., and Carolei, A. 1979. The pigmentary system of planaria. I. Morphology. Cell Tissue Res. 199: 197-202.
77. Palmberg, I. 1990. Differentiation in living flatworms. Ultrastructural, immunocytochemical and autoradiographic studies of asexually reproducing and regenerating Microstomum lineare (Macrostomida). Acta Acad. Abo. Ser B Math. Phys. 50(8): 1-50.
78. Pedersen, K.J. 1963. Slime-secreting cells of planarians. Ann. N.Y. Acad. Sci. 106: 424-443.
79. Pedersen, K.J. 1966. The organization of the connective tissue of Discocelides langi (Turbellaria, Polycladida). Z. Zellforsch. Mikrosk. Anat. 71: 94-117.
80. Pedersen, K.J. 1983. Fine structural observations on the turbellarians Stenostomum sp., and Microstomum lineare with special reference to extracellular matrix and connective tissue systems. Acta Zool. (Stockh.) 64: 177-190.
81. Pedersen, K.J. 1991. Invited review: structure and composition of basement membranes and other basal matrix systems in selected invertebrates. Acta Zool. (Stockh.) 72: 181-202.
82. Peter, R., Ladurner, P., and Rieger, R. 2001. The role of stem cell strategies in coping with environmental stress and choosing between alternative reproductive modes: Turbellaria rely on a single cell type to maintain individual life and propagate species. Mar. Ecol. 22(1-2): 35-51.
83. Popiel, I. 1978. The ultrastructure of the daughter sporocyst of Cercaria littorinae saxatilis V Popiel, 1976. (Digenea: Microphallidae). Z. Parasitenkd. 56: 167-173.
84. Popiel, I., Irving, D.L., and Basch, P.F. 1985. Wound healing in the trematode Schistosoma. Tissue Cell, 17: 69-78.
85. Prudhoe, S. 1985. A monograph on polyclad Turbellaria. Oxford University Press, Oxford.
86. Raikova, O.I., Reuter, M., Kotikova, E.A., and Gustafsson, M.K.S. 1998. A commissural brain! The pattern of 5-HT immunoreactivity in Acoela (Plathelminthes). Zoomorphology (Berl.), 118: 69-77.
87. Raikova, O.I., Reuter, M., and Justine, J.-L. 2001. Contributions to the phylogeny and systematics of the Acoelomorpha. In Interrelationships of the Platyhelminthes. Edited by D.T.J. Littlewood and R.A. Bray. Taylor & Francis, London. pp. 13-23.
88. Ramasamy, P., Hanna, R.E.B., and Threadgold, L.T. 1987. Scanning and transmission electron microscopic studies of the surface of Vallisia indica (Monogenea, Polyopisthocotylea). Int. J. Parasitol. 17: 1187-1195.
89. Reisinger, E. 1924. Die Gattung Rhynchoscolex. Z. Morphol. Oekol. Tiere, 1: 1-37.
90. Reisinger, E., Cichocki, I., Erlach, R., and Szyskowitz, T. 1974. Ontogenetische Studien an Turbellarien: ein Beitrag zur Evolution der Dotterverarbeitung im ektolecitalen Ei. Z. Zool. Syst. Evolutionsforsch. 12: 161-195, 241-278.
91. Reiter, D., Boyer, B., Ladurner, P., Mair, G., Salvenmoser, W., and Rieger, R. 1996. Differentiation of the body-wall musculature in Macrostomum hystricinum marinum and Hoploplana inquilina (Plathelminthes), as models for muscle development in lower Spiralia. Roux's Arch. Dev. Biol. 205: 410-423.
92. Rieger, R.M. 1981. Morphology of the Turbellaria at the ultrastructural level. Hydrobiologia, 84: 213-229.
93. Rieger, R.M. 1998. 100 years of research on "Turbellaria". Hydrobiologia, 383: 1-27.
94. Rieger, R.M., and Doe, D.A. 1975. The proboscis armature of Turbellaria-Kalyptorhynchia, a derivative of the basement lamina? Zool. Scr. 4: 25-32.
95. Rieger R.M., and Ladurner, P. 2001. Searching for the stem species of the Bilateria. Belg. J. Zool. 131(Suppl. 1): 27-34.
96. Rieger, R.M., and Ladurner, P. 2003. The significance of muscle cells for considering the origin of mesoderm in Bilateria. Integr. Comp. Biol. 43(1): 47-54.
97. Rieger, R.M., and Rieger, G.E. 1976. Fine structure of the archiannelid cuticle and remarks on the evolution of the cuticle within the Spiralia. Acta. Zool. (Stockh.), 57: 53-68.
98. Rieger, R.M., and Sterrer, W. 1975. New spicular skeletons in Turbellaria, and the occurrence of spicules in marine meiofauna. Z. Zool. Syst. Evolutionsforsch. 13: 207-248.
99. Rieger, R., Salvenmoser, W., Legniti, A., Reindl, S., Adam, H., Simonsberger, P., and Tyler, S. 1991a. Organization and differentiation of the body-wall musculature in Macrostomum (Turbellaria, Macrostomidae). Hydrobiologia, 227: 119-129.
100. Rieger, R.M., Tyler, S., Smith, J.P.S., and Rieger, G. 1991b. Platyhelminthes: Turbellaria. In Microscopic anatomy of invertebrates. Edited by F.W. Harrison and B.J. Bogitsh. Wiley-Liss, New York. pp. 7-140.
101. Rieger, R.M., Salvenmoser, W., Legniti, A., and Tyler, S. 1994. Phalloidin-rhodamine preparations of Macrostomum (Plathelminthes): functional morphology and postembryonic development of the musculature. Zoomorphology (Berl.), 114: 133-148.
102. Rieger, R.M., Legniti, A., Ladurer, P., Reiter, D., Asch, E., Salvenmoser, W. et al. 1999. Ultrastructure of neoblasts in microturbellaria: significance for understanding stem cells in free-living Platyhelminthes. Invertebr. Reprod. Dev. 35: 127-140.
103. Rohde, K. 1972. The Aspidogastrea, especially Multicotyle purvisi Dawes 1941. Adv. Parasitol. 10: 77-151.
104. Rohde, K., and Watson, N.A. 1995. Sensory receptors and epidermal structures of a meiofaunal turbellarian (Proseriata, Monocelididae, Minoninae). Aust. J. Zool. 43: 69-81.
105. Rohde, K., Watson, N.A., and Cannon, L.R.G. 1988. Comparative ultrastructural studies of the epidermis, sperm and nerve fibres of Cleistogamia longicirrus and Seritia stichopi (Rhabdocoela, Umagillidae). Zool. Scr. 17: 337-345.
106. Ruiz-Trillo, I., Riutort, M., Littlewood, D.T.J., Herniou, E.A., and Baguñà, J. 1999. Acoel flatworms: earliest extant bilaterian metazoans, not members of Platyhelminthes. Science (Wash., D.C.), 283: 1919-1923.
107. Ruiz-Trillo, I., Paps, J., Loukota, M., Ribera, C., Jondelius, U., Baguñà, J., and Riutort, M. 2002. A phylogenetic analysis of myosin heavy chain type II sequences corroborates that Acoela and Nemertoderematida are basal bilaterians. Proc. Natl. Acad. Sci. U.S.A. 99: 11246-11251.
108. Ruppert, E.E., and Barnes, R.D. 1994. Invertebrate zoology. Saunders, Philadelphia, Pa.
109. Sakurai, T., and Ishii, S. 1995. An electron microscope study of primary epidermis formation in freshwater planarian embryos. Hydrobiologia, 305: 159.
110. Salvenmoser, W., Riedl, D., Ladurner, P., and Rieger, R. 2001. Early steps in the regeneration of the musculature in Macrostomum sp. (Macrostomorpha). Belg. J. Zool. 131(Suppl. 1): 105-109.
111. Sánchez Alvarado, A. 2000. Regeneration in the metazoans: why does it happen? Bioessays, 22: 578-590.
112. Skaer, R.J. 1961. Some aspects of the cytology of Polycelis nigra. Q. J. Microsc. Sci. 102: 295-318.
113. Skaer, R.J. 1965. The origin and continuous replacement of epidermal cells in the planarian Polycelis tenuis (Iijima). J. Embryol. Exp. Morphol. 13: 129-139.
114. Smith, J.P.S., and Tyler, S. 1985. The acoel turbellarians: kingpins of metazoan evolution or a specialized offshoot? In The origins and relationships of lower invertebrates. Edited by C. Conway Morris, J.D. George, R. Gibson, and H.M. Platt. Oxford University Press, Oxford. pp. 123-142.
115. Smith, J.P.S., and Tyler, S. 1986. Frontal organs in the Acoelomorpha (Turbellaria): ultrastructure and phylogenetic significance. Hydrobiologia, 132: 71-78.
116. Smith, J.S., Tyler, S., Thomas, M.B., and Rieger, R. 1982. The nature of turbellarian rhabdites: phylogenetic implications. Trans. Am. Microsc. Soc. 101: 209-228.
117. Smith, J.P.S., Tyler, S., and Rieger, R.M. 1986. Is the Turbellaria polyphyletic? Hydrobiologia, 132: 13-21.
118. Southgate, V.R. 1970. Observations on the epidermis of the miracidium and on the formation of the tegument of the sporocyst of Fasciola hepatica. Parasitology, 61: 177-199.
119. Thaler, M., Gschwentner, R., Ladurner P., Nimeth, K., Salvenmoser, W., and Rieger, R. 2002. Ultrastrucrural aspects of stem cells in Convoluta pulchra (Acoela, Acoelomorpha). In Cells IV. Edited by J. Berger. Kopp Publishing, Ceske Budejovice, Czech Republic. p. 136.
120. Threadgold, L.T. 1984. Parasitic platyhelminths. In Biology of the integument. Vol. I. Invertebrates. Edited by J. Bereiter-Hahn, A.G. Matoltsy, and K.S. Richards. Springer-Verlag, Berlin, Germany. pp. 132-191.
121. Tyler, S. 1981. Development of cilia in embryos of the turbellarian Macrostomum. Hydrobiologia, 84: 231-239.
122. Tyler, S. 1984. Turbellarian platyhelminths. In Biology of the integument. Vol. I. Invertebrates. Edited by J. Bereiter-Hahn, A.G. Matoltsy, and K.S. Richards. Springer-Verlag, Berlin, Germany. pp. 112-131.
123. Tyler, S. 1988. The role of function in determination of homology and convergence - examples from invertebrate adhesive systems. Fortschr. Zool. 36: 331-347.
124. Tyler, S. 2003. Epithelium - the primary building block for metazoan complexity. Integr. Comp. Biol. 43(1): 55-63.
125. Tyler, S., and Rieger, R.M. 1977. Ultrastructural evidence for the systematic position of the Nemertodermatida (Turbellaria). Acta Zool. Fenn. 54: 193-207.
126. Tyler, S., and Rieger, R.M. 1999. Functional morphology of musculature in the acoelomate worm, Convoluta pulchra (Plathelminthes). Zoomorphology (Berl.), 119: 127-141.
127. Tyler, S., and Tyler, M.S. 1997. Origin of the epidermis in parasitic platyhelminths. Int. J. Parasitol. 27: 715-738.
128. Uglem, G.L., and Just, J.J. 1983. Trypsin inhibition by tapeworms: antienzyme secretion or pH adjustment. Science (Wash., D.C.), 220: 79-81.
129. von Graff, L. 1904-1908. Acoela und Rhabdocoela. Plathelminthes III. Turbellaria. In Bronn's Klassen und Ordnungen des Tierreichs. Vol. IV. Abt. 1c. Winter'sche Verlagsbuchhandl, Leipzig. pp. 1733-2599.
130. Westblad, E. 1942. Studien ueber skandinavische Turbellaria Acoela. II. Ark. Zool. 33A(14): 1-48.
131. Westblad, E. 1949. On Meara stichopi (Bock) Westblad, a new representative of Turbellaria Archoophora. Ark. Zool. 1: 43-57.
132. Xylander, W.E.R. 1987. Ultrastructure of the lycophora larva of Gyrocotyle urna (Cestoda, Gyrocotylidea). I. Epidermis, neodermis anlage and body musculature. Zoomorphology (Berl.), 106: 352-360.
133. Xylander, W.E.R. 1996. Neodermata. In Spezielle Zoologie. Erster Teil: Einzeller und Wirbellose Tiere. Edited by W. Westheide and R. Rieger. Gustav Fischer Verlag, Stuttgart, Germany. pp. 230-258.
134. Xylander, W.E.R. 2001. The Gyrocotylidea, Amphilinidea and the early evolution of the Cestoda. In Interrelationships of the Platyhelminthes. Edited by D.T.J. Littlewood and R.A. Bray. Taylor and Francis, London. pp. 103-111.
135. Younossi-Hartenstein, A., and Hartenstein, V. 2000. The embryonic development of the polyclad flatworm Imogine mcgrathi. Dev. Genes Evol. 210: 383-398.
136. Younossi-Hartenstein, A., and Hartenstein, V. 2001. The embryonic development of the temnocephalid flatworms Craspedella pedum and Diceratocephala boschmai. Cell Tissue Res. 304: 295-310.