Scanning electron microscopy provided much details to the external morphology of Artemia. The whole body of Artemia is covered by an extremely thin exoskeleton. In the larval stages the cuticle is 0.3 to 1.0 µm thin and probably has a similar appearance in all regions of the integument. The nervous system of Artemia is of the typical primitive Branchiopod type consisting of a dorsal brain, or supraesophageal ganglion, circumesophageal connectives, and a double ventral row of segmental paired ganglia united longitudinally by connectives and laterally by a large anterior and a smaller posterior commissure. R. Benesch extensively describes both the larval and adult muscular system and endos-keleton, and compares it to the description of the adult Artemia by C. Claus, and to Chirocephalus. As soon as differentiating muscle cells and coelom appear in the segments the presumptive, connective tissue can be discerned by its chromatin loaded nuclei.