98 THE WORLD OF THE SEA. 
lamellar expansions of the same material. It owes its popular 
name to a fancied resemblance to organ pipes. (See engraving, 
page 100.) 
aS 
SS 
ate rad 
A PORITIDA. 
(Porites mordax. ) 
The polypes themselves are a grass green. Their tentacles 
are furnished on each edge with sixty or eighty pulpy, tongue-like 
papille. 
The Gorgonideé have their cortex so filled with calcareous and 
