EXPLANATION OF PLATE XXIIL 



Fig-. I. Ecliinoclictyuni clegaus, Lendenfeld ; x 1/3. 



Fig. _'. Crella incrustans, Carter, var. digitata, var. nov., 

 encrusting a bivalve; viewed from the side; x i/.^. 



Fig. 3. Crella mcrnstans, \ar. arenacea, Carter; x 4/9. 



Showing the irregularity of form assumed by the 

 shallow-water New South Wales representatives of 

 the species ; the dermal encrustation is almost en- 

 tirely denuded ; the surface-grooves are less apparent 

 in the figure than in the specimen itself. 



