A MONOGRAPH 



BRITISH SPONGIADJE. 



J. S. BOWERBANK, LL.D., 



F.E-S., r.L.S., r.Q.S., T-.Z.S., F.E.A S., 



MEWBKE OF THE ENTOMOLOGTCAL SOCIKTY OF LONDON ■, OF THK ROYAL MIC-ROSCOPICAL SOCIETY 



OF LONDON ; CORRESPONDING MEMBER OF THE DUBLIN UNIVERSITY 



ZOOLOGICAL AND BOTANICAL ASSOCIATION; OK THE PLYMOUTH INSTITUTION, AND 



DEVON AND CORNWALL NATUHAL HISTORY SOCIETY, ETC. KTC. 



VOL, III. 



LONDON: 

 PRINTED FOR THE EAY SOCIETY, 



MECCCLXXIV. 



