418 Prof. G. Retzius. Principles of the [June 15, 
substance in their most delicate ramifications, where they did not unite with 
each other, and on the whole did not form a network (reticulum), but a twist- 
work (plexus). One could also trace the stem-processes of the nerve-cells even 
in their various courses through the ganglions towards the periphery (fig. 1). 
‘ 
Fic. 1.—A Part of the Ventral Nervous Chain of the common Crawfish (Astacus), 
showing a ganglion with coloured (black) nerve-cells and their processes. 
