Zoomorphology

, Volume 101, Issue 1, pp 1–15

Ultrastructure of multiciliated collar cells in the pilidium larva of Lineus bilineatus (Nemertini)

  • Carl-Erik Cantell
  • Åke Franzén
  • Terry Sensenbaugh
Article

Summary

The ultrastructure of the apical plate of the free-swimming pilidium larva of Lineus bilineatus (Renier 1804) is described with particular reference to the multiciliated collar cells. In the multiciliary collar cells there are several, up to 12, cilia surrounded by a collar of about 20 microvilli extending from the cells' apical surface. The cilia have the typical 9+2 axoneme arrangement and are equipped with striated caudal rootlets extending from the basal bodies. No accessary centriole or rostral rootlet were observed. Microvilli surrounding the cilia are joined in a cylindrical manner by a mucus-like substance to form a collar. In comparison with many sensory receptor cells built on a collar cell plan the multiciliary collar cells of the pilidium larva apical plate are rather simple and unspecialized. In other pilidium larvae monociliated collar cells are found in the apical plate. The possible function and phylogenetic implications of multiciliated collar cells in Nemertini are briefly discussed.

List of Abbreviations

a

axoneme

b

basal body

c

cilia or flagella

d

desmosome

G

Golgi apparatus

m

mitochondria

mf

microfilaments

mu

mucus

mv

microvilli

n

nucleus

nt

neurotubules

pm

plasma membrane

r

rootlet

ri

ribosomes

v

secretory vesicles

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Brill B (1973) Untersuchungen zur Ultrastruktur der Choanocyte von Ephydatia fluviatilis L. Z Zellforsch Mikrosk Anat 144:231–245Google Scholar
  2. Cantell C-E (1969) Morphology, development, and biology of the pilidium larvae (Nemertini) from the Swedish West Coast. Zool Bidr Upps 38:61–112Google Scholar
  3. Coe WR (1899) Development of the pilidium of certain Nemerteans. Trans Conn Acad 10:235Google Scholar
  4. Dilly PN (1972) The structures of the tentacles of Rhabdopleura compacta (Hemichordata) with special reference to neurociliary control. Z Zellforsch Mikrosk Anat 129:20–39Google Scholar
  5. Ehlers U, Ehlers B (1977) Monociliary receptors in interstitial Proseriata and Neorhabdocoela (Turbellaria Neoophora). Zoomorphologie 86:197–222Google Scholar
  6. Ehlers U, Ehlers B (1978) Paddle cilia and discocilia — genuine structures? Cell Tissue Res 192:489–501Google Scholar
  7. Feige W (1969) Die Feinstruktur der Epithelien von Ephydatia fluviatilis. Zool Jahrb Abt Anat Ontog Tiere 86:177–237Google Scholar
  8. Franzén Å (1956) On spermiogenesis, morphology of the spermatozoon, and biology of fertilization among invertebrates. Zool Bidr Upps 31:355–482Google Scholar
  9. Franzén Å (1982) Spermatogenesis and sperm function. Nemertini. In: Adiyodi KG (ed) Reproductive Biology of Invertebrates. Vol II. John Wiley & Sons, Ltd, New York (in press)Google Scholar
  10. Hibberd DJ (1975) Observations on the ultrastructure of the choanoflagellate Codosiga botrytis (Ehr.) Saville-Kent with special reference to the flagellar apparatus. J Cell Sci 17:191–219Google Scholar
  11. Knapp MF, Mill PJ (1971) The fine structure of ciliated sensory cells in the epidermis of the earthworm Lumbricus terrestris. Tissue Cell 3:623–636Google Scholar
  12. Lyons KM (1973a) Collar cells in planula and adult tentacle ectoderm of the solitary coral Balanophyllia regia (Anthozoa Eupsammidae). Z Zellforsch Mikrosk Anat 145:57–74Google Scholar
  13. Lyons KM (1973b) Evolutionary implications of collar cell ectoderm in a coral planula. Nature 245:50–51Google Scholar
  14. Moritz K, Storch V (1971) Elektronenmikroskopische Untersuchungen eines Mechanoreceptors von Evertebraten (Priapuliden, Oligochaeten). Z Zellforsch Mikrosk Anat 117:226–234Google Scholar
  15. Müller J (1847) Über einige neue Tierformen der Nordsee. Arch Anat Physiol (1847) pp 157–179Google Scholar
  16. Nørrevang A, Wingstrand KG (1970) On the structure of choanocyte-like cells in some echinoderms. Acta Zool (Stockholm) 51:249–270Google Scholar
  17. Rieger RM (1976) Monociliated epidermal cells in Gastrotricha: Significance for concepts of early metazoan evolution. Z Zool Syst Evolut-forsch 14:198–226Google Scholar
  18. Storch V (1979) Contributions of comparative ultrastructural research to problems of invertebrate evolution. Am Zool 19:637–645Google Scholar
  19. Tardent P, Schmid V (1972) Ultrastructure of mechanoreceptors of the polyp Coryne pintneri (Hydrozoa, Athecata). Exp Cell Res 72:265–275Google Scholar
  20. Tyler S (1976) Comparative ultrastructure of adhesive systems in the Turbellaria. Zoomorphologie 84:1–76Google Scholar
  21. Vader W, Lönning S (1975) The ultrastructure of the mesenterial filaments of the sea anemone, Bolocera tuediae. Sarsia 58:79–88Google Scholar
  22. Welsch U, Storch V (1976) Comparative animal cytology and histology. Sidgwick and Jackson, LondonGoogle Scholar
  23. Wilson CB (1900) The habits and early development of Cerebratulus lacteus. Q J Microsc Sci (2) 43:97–198Google Scholar
  24. Woollacott RM, Zimmer RL (1971) Attachment and metamorphosis of the cheilo-ctenostome bryozoan Bugula neritina (Linné). J Morphol 134:351–382Google Scholar

Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Carl-Erik Cantell
    • 1
  • Åke Franzén
    • 2
  • Terry Sensenbaugh
    • 1
  1. 1.Institute of ZoologyUppsala UniversityUppsalaSweden
  2. 2.Section of Invertebrate ZoologySwedish Museum of Natural HistoryStockholmSweden

Personalised recommendations