AUTHOR'S PREFACE, 



At the request of the Keeper of the Geological Department in the Natural-History 

 Museum, I commenced, in the early part of 1881, the study of the collection of 

 Fossil Sponges in the Museum with the view of arranging them systematically and 

 preparing a simple Catalogue of their specific names and references. Hitherto no 

 attempt had been made to place the Fossil Sponges in scientific order, and with the 

 exception of the limited portion of the Collection formerly exhibited in the Museum 

 at Bloomsbury, which had been mostly included in the comprehensive genera of 

 Spongia, Scfphia, Manon, &c., the greater number of the specimens simply retained 

 the labels of the localities and horizons from whence they had been derived. A 

 preliminary examination made evident the fact that numerous specimens, more 

 particularly those from British strata, were either quite new to science or had been 

 described and figured in such an imperfect manner that their real characters were 

 unknown. Under these circumstances a mere catalogue of names and references, 

 such as had been at first proposed, would have been quite valueless ; and, with the 

 consent of the Trustees, it was decided to enlarge the plan and embrace in the 

 Catalogue condensed descriptions of all the species from British strata and of the 

 new species from foreign localities, with figures of all the new forms as well as of 

 those which had been either inadequately figured previously, or of which it was 

 desirable to illustrate the minute structure. To carry out this plan involved a far 

 greater expenditure of time and work than was at first anticipated ; but it is hoped 

 that the results of nearly three years' study will be to place our knowledge of this 

 group of fossils on a more satisfactory basis than hitherto. 



The Museum collection includes examples of a very large majority of all the 

 species of Fossil Sponges at present known, and, as may naturally be supposed, it is 

 especially rich in those occurring in the rocks of this country. It contains amongst 

 others the typical collections of William Smith, " The Father of English Geology," 

 Toulmin Smith, Mantell, Bowerbank, and Cunuington. The fossil sponges from the 

 Jurassic and Cretaceous strata of France, Switzerland, and Germany are also well 

 represented. With a few unimportant exceptions, the Sponges from these countries 

 have been clearly figured in the works of Goldfuss, Roemer, Michelin,Quenstedt, Eeuss, 

 Geinitz, de Loriol, Fromentel, and others ; and as their minute spicular structure has 



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