Abstract
In the embryos of glossiphoniid leeches, as in other spirally cleaving embryos, there is ambiguity as to how the early cleavages in the embryo relate to the bilateral symmetry of the adult. Traditionally, we have aligned the B–D axis of the 4-cell stage with the anterior—posterior (A–P) axis of the adult. This requires that the first cleavage be skewed with respect to the A–P axis. Here, we re-examine the fates and behaviours of early blastomeres and conclude that a more accurate representation of the embryo is to have the first cleavage plane transverse to the A–P axis.
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© 1999 Springer Science+Business Media Dordrecht
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Weisblat, D.A. (1999). Cellular origins of bilateral symmetry in glossiphoniid leech embryos. In: Dorresteijn, A.W.C., Westheide, W. (eds) Reproductive Strategies and Developmental Patterns in Annelids. Developments in Hydrobiology, vol 142. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-2887-4_17
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DOI: https://doi.org/10.1007/978-94-017-2887-4_17
Publisher Name: Springer, Dordrecht
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