On the Microanatomy of the Cephalic Nervous System of Nereidae (Polychaeta), with a Preliminary Discussion of Some Earlier Theories on the Segmentation of the Polychaete Brain
Earlier papers dealing with the microanatomy of the nereid brain have been studied. On this basis a re‐investigation of the cephalic nervous system and of the innervation and homologues of the anterior end appendages of these animals appeared necessary: the existing literature proved insufficient fo...
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Published in | Acta zoologica (Stockholm) Vol. 74; no. 2; pp. 145 - 172 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
Oxford, UK
Blackwell Publishing Ltd
01.03.1993
Elsevier Science |
Subjects | |
Online Access | Get full text |
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Summary: | Earlier papers dealing with the microanatomy of the nereid brain have been studied. On this basis a re‐investigation of the cephalic nervous system and of the innervation and homologues of the anterior end appendages of these animals appeared necessary: the existing literature proved insufficient for detailed comparisons with other polychaete families and many earlier statements were quite contradictory. In the present paper, the brain commissures and the innervation of, inter alia, the antennae and the palps of Neanthes virens and Nereis pelagica are described. Special attention was paid to the roots of the circum‐oesophageal connectives and the ganglia in this part of the nervous system. The results, summarized in schematic diagrams and tables, are compared with corresponding observations in 14 other polychaete families. In a discussion of the architecture of the polychaete nervous system as a phylogenetic instrument, the supposed segmentation of the polychaete brain is questioned and the idea that the configuration of the polychaete nervous system offers support to the cyclomer theory is rejected. Other conclusions concerning the relationships within the Polychaeta are pointed out. |
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Bibliography: | istex:C34A67370E84B261A9E81D91F9E3A94EEBA98C45 ArticleID:AZO1231 ark:/67375/WNG-LW0C9GXF-P |
ISSN: | 0001-7272 1463-6395 |
DOI: | 10.1111/j.1463-6395.1993.tb01231.x |