A MONOGRAPH 



OF THE 



BRITISH SPONGIAD^. 



SYNOPSIS OF GENERA. 



Class PORIF ERA, Grant, 

 Order L CALCAREA. 



Genera. 1. Grantia. 



2. Leucosolenia. 



3. Leuconia. 



4. Leucogipsia. 



1. Grantia, Fleming. 



Sponge. Furnished with a central cloaca, parietes con- 

 structed of interstitial cells, more or less regular 

 and angular in form, disposed at right angles to the 

 external surface, and extending in length from the 

 outer to very near the inner surface of the sponge, 

 where each terminates in a single osculum. Vol. I, 

 p. 162. 



