Early embryonic development of the priapulid worm Priapulus caudatus

@article{Wennberg2008EarlyED,
  title={Early embryonic development of the priapulid worm Priapulus caudatus},
  author={Sofia A. Wennberg and Ralf Janssen and Graham E. Budd},
  journal={Evolution \& Development},
  year={2008},
  volume={10}
}
SUMMARY The early cleavage up to gastrulation is described here for the priapulid worm Priapulus caudatus, contradicting and clarifying earlier partial reports on this topic. The cleavage pattern up to gastrulation is highly symmetrical, total, subequal, radial, and stereotypical. Gastrulation is intermediate between epiboly and invagination, and the mesendoderm may be derived from both cells of the first cleavage, thus differing significantly in its origin from that of many other protostomes… 
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