PLATE VIIL 



" IsoDiOTTA FEEULA, Bowerbauk. 



Figs. 1 and 2. — Represent the type-specimena of the 

 species. Natural size. 



Kg. 3. — A skeleton spiculum. X 264 linear." 



" IsoDiOTTA CEASSA, Bowevhank. 



Fig. 4. — Represents the type-specimen. Natural 

 size. 



Fig. 6. — A small portion of the dermal membrane, 

 exhibiting its reticulated structure. 



Fig. 6. — A skeleton spiculum." 



