KSSAY ON SPONGES. 



71 



It would appear that Mr Ellis found much dif- 

 ficulty in ascertaining the species of this genus. 

 By him seven only seem to have been described, 

 viz. coronata, oculata, tomentosa, stuposa, cristata^ 

 palmata, and botryoides. In addition to these, 

 Berkenhout has given dkhotoma ; Mr Sowerby, 

 in his British Miscellany, enumerates three others : 

 pukhella, cancellata, and compacta ; and, lastly, 

 we find infundibuUformis, voitilabrum, and com- 

 pr^es&a, described as British by Professor Jame- 

 son in the first volume of the Memoirs of the 

 Wernerian Society ; making together fourteen 

 species. 



It will be noticed, that, in the following pages^ 

 I have almost twice that number ; and of those 

 which possess sufficiently strong specific characters 

 to be defined by the pencil, figures have been 

 given; 



With respect to the nature of sponges, there 

 has been considerable difference of opinion ; but, 

 in the present era of natural history, it is pretty 

 generally allowed, that they are truly of an animal 

 substance, extremely torpid, and for the most part, 

 if not wholly, destitute of visible motion. With 

 considerable attention to some species taken fresh 

 from the sea, and others that I have examined in 

 the cavities of their native rocks, still immersed in 

 their natural element, not the smallest motion was 

 perceptible, nor were there any appearances of in- 

 ternal action , for such would have produced some 



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