PLATE LXTX. 



FKi. 



1 . Alcyonidium hirsutum, p. 360. Of the natural size. 



2. A portion of the surface magnified. 



3. The dried crust of Hydractinia echinata, p. 34, invest- 



ing a shell of Buccinum un datum. 



4. A small piece of this crust magnified. 



5. Oliona celata of Grant, with (6) its siliceous spicula. 



See my History of British Sponges and Lithophytes, 

 p. 125. 





