New York
MACMILLAN AND CO.
AND LONDON
1895
All rights reserved
“Why, you might take to some light study: conchology, now; I always think that must be a light study.”
George Eliot, Middlemarch.
Copyright, 1895,
By MACMILLAN AND CO.
Norwood Press:
J. S. Cushing & Co.—Berwick & Smith.
Norwood, Mass., U.S.A.
PREFACE TO THE MOLLUSCA
The general plan of classification adopted in this work is not that of any single authority. It has been thought better to adopt the views of recognised leading specialists in the various groups, and thus place before the reader the combined results of recent investigation. This method may, perhaps, occasion a certain number of small discrepancies, but it is believed that the ultimate effect will be to the advantage of the student.
The classification adopted for the recent Cephalopoda is that of Hoyle (‘Challenger’ Reports, Zoology, vol. xvi.), for the fossil Cephalopoda (Nautiloidea) that of Foord (Catalogue of the Fossil Cephalopoda in the British Museum, 1888–91), and (Ammonoidea) P. Fischer (Manuel de Conchyliologie, 1887). In the Gasteropoda the outlines are those adopted by Pelseneer (Mém. Soc. Malacol. Belg. xxvii. 1894), while the details are derived, in the main, from P. Fischer. The Amphineura, however, have not been regarded as a separate class. The grouping of the Nudibranchiata is that of Bergh (Semper, Reisen im Archipel der Philippinen, ii. 3). The Pelecypoda are classified according to Pelseneer’s most recent grouping.