Figure 8

Simplified diagram of neural development in Hypsibius dujardini. Ventral view; anterior is up in all images. Hollow arrowheads indicate first neurons of the stomodeal nervous system (red). Solid arrowheads point to neurites innervating the circumoral sensory field. Asterisks indicate buccal sensory organs. Black, central nervous system; blue, peripheral nervous system. Developmental series, from (A-D). Abbreviations: an, anterior peripheral nerve; av, anteroventral cells; br, brain cells; c1, central commissure of the first trunk ganglion; cb, developing central brain neuropil (arising from a single commissure); g1 to g4, anlagen of trunk ganglia 1 to 4; lg, leg ganglion; nr, circumbuccal nerve ring; oc, outer connective; pl, posterior leg nerve.