SUPPLEMENT 



VOL. II, 'MONOGRAPH OF BRITISH SPONGIADiE. 



The following portion of the work is descriptive and 

 illustrative of new species of British Sponges that have 

 been discovered since the pul)lication of vol. ii, and also 

 of a few species that were published in that volume 

 which it has been thought advisable, upon a reconsi- 

 deration of then' structures and of the chai^acters 

 first assigned to them, to remove to other Genera, with 

 which their anatomical peculiarities were more closely 

 in accordance. To these alterations of Genera the 

 descriptions of the respective plates will readily lead 

 the student. 



