BRITISH SPONGIADjE. 17 



DESCRIPTIONS 



OF 



THE SPECIES 



Order I CALCAREA. 

 Genus Grantia, Fleming. 



1. Grantia compressa, Fleming. 



2. ciliata, Fleming. 



3. ensata, Bowerbank. 



4. fessellata, Bowerbank. 



1. Grantia compressa. 



Sponge. Compressed, foliaform, slightly pedicelled ; surface 

 even, armed with flecto-clavate spicula. Cloaca ex- 

 panded to the form of the sponge, very large, armed 

 internally with spiculated triradiated spicula ; spicular 

 ray short, attenuated. Mouths of cloaca from one to 

 seven or eight, simple, unarmed. Oscula on the sides 

 of the cloaca in depressed areas ; as numerous as the 

 interstitial cells. Pores inconspicuous. Skeleton : 

 spicula equiangular and elongo-equiangulated, tri- 

 radiate, the latter frequently having the two shorter 

 radii exflected. 



