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XLI. On the Anatomy and Physiology of the Spongiadce. — Part III. On the Generie 
Characters, the Specific Characters, and on the Method of Examination. 
By J. S. Boweebank, LL.B., F.B.S., F.L.S. &c. 
Eeceiyed June 18, — Bead June 19, 1862. 
"While the arrangement of other branches of natural history has occupied the attention 
of some of the most laborious and talented naturalists of every age, the Spongiadge 
appear to have scarcely attracted sufficient attention to excite any Avriter on natural 
history to a serious attempt at a systematic classification. This neglect has not arisen 
from any incapacity for a definite arrangement on the part of the Spongiadae, as the 
organic differential characters of the numerous groups into which, by careful exami- 
nation, they may be readily divided are as varied and as widely removed from each 
other as are the strikingly distinct and well defined divisions of the Corallidse ; and the 
number of species I believe to be very much greater than those of the latter class. Of 
British species alone I am already acquainted with 150 or more ; and new ones are con- 
tinually being discovered by the aid of the dredge. It becomes therefore a matter of 
necessity that we should classify their permanent varieties of structure, and found on 
them a series of orders, suborders, and genera, and through these subdivisions become 
enabled to recognize more readily the very numerous species of these animals which 
abound in all parts of the world. 
De Blainville proposed to include the whole of the Spongiadse under the designation 
of Amorphozoa; but this term is objectionable, as all sponges cannot be considered as 
shapeless — on the contrary, many genera and species exhibit much constancy in their 
form. Neither can the term be justly applied to their internal structure, as we fin d in 
Grantia, Geodia, Tethea, and other genera regular and systematical structures which 
are very far removed from shapelessness. I have therefore thought it advisable to adopt 
Dr. Geant’s designation of Porifera, a term which embraces the whole of the Spongiadae, 
and which is truly descriptive of the most essential general action of the animal’s power 
and mode of imbibing nutriment, which in every species with which I am acquainted is, 
by a series of minute pores distributed over the external membrane of the sponge. 
Besides this universally existent character there are others which are strikingly charac- 
teristic of the class, although not so universally prevalent as the porous one. -Thus 
the skeletons of the Spongiadae are always internal, but in the material and mode of 
construction they vary to a very considerable extent. Sponges may therefore be defined 
as fixed, aquatic, polymorphous animals, inhaling and imbibing the surrounding element 
through numerous contractile pores situated on the external surface; conveying it 
MDCCCLXn. 7 I 
