uûth some Remarks on the Nature of tlie Spongiœ Marinœ. 407 



them the opportunity, would, from their own researches on these productions, 

 furnish us with more full and accurate details, and thereby lay the foundation 

 for a separate and copious work, — indeed a complete monograph, — on the 

 ISponges ; recollecting also the concluding remark of the late Professor Pallas, 

 which is at this day even far from being inapplicable: "Quibus Spongiarum 

 fertiles oceani tractus lustrare contigerit bene multa invenient quae superad- 

 dant et magnum in scientia naturali explebit hiatum, qui plenam Spongiarum 

 historian! dabit, gnaris gratissimam certe futuram atque utilissimis observa- 

 tionibus feracissimam*." 



* Elench. Zooph., p. 377. 



VOL. XVIII. 3 H 



