In Part I of this series of "Studies in Australian Athecate Hydroids," I described and figured the external characters of a new species of Myriothela, M. harrisoni, from the South Coast of New South Wales. The specimens, which were collected on the undersides of rocks below low-water mark at Bulli, were fixed in sublimate-acetic-alcohol and transferred to 70% alcohol. Serial sections of the hydranths with their attached blastostyles and gonophores were cut in a transverse direction, and afterwards stained with Ehrlich's haematoxylin followed by eosin. Grubler's picro-carmine proved a very useful stain for the differentiation of the fibrillar structure of the supporting lamella in the capitulum of the tentacles. For the study of the nematocysts, some of the sections were stained in methylene blue and orange G. The sections were cut in thicknesses varying from 6 to 8 microns.