Additional file 1: of The anatomy and development of the nervous system in Magelonidae (Annelida) â insights into the evolution of the annelid brain

Magelona alleni, histological cross sections (5â Iźm), Masson-Goldner Trichrome, frontal (A) to caudal (C). A: The brain (br) surrounds the frontally located coelomic cavities (co). Intermediate filaments (if) run through the neuropil. B: More posterior the brain consist of a dorsal part (dpbr) which gives rise to dorsolateral parts of the brain (dlpbr) which connect the dorsal brain to the ventral part of the brain. mo: mouth opening. C: More posterior the cns is composed of paired lateral medullary cord (lmc) which run caudally rectangular to the brain inside the epidermis (ep). Giant fibres (gf) initially are small. A cluster of enlarged neurons (S3) is present in the dorso- lateral part. bl: basal lamina; if: intermediate filaments. (PDF 10348 kb)