[Illustration: BRITISH MUSEUM (NATURAL HISTORY) Ground Floor. ] A GUIDE TO THE SHELL AND STARFISH GALLERIES (MOLLUSCA, POLYZOA, BRACHIOPODA, TUNICATA, ECHINODERMA, AND WORMS). DEPARTMENT OF ZOOLOGY. BRITISH MUSEUM (NATURAL HISTORY), CROMWELL ROAD, LONDON, S.W. _WITH NUMEROUS ILLUSTRATIONS._ PRINTED BY ORDER OF THE TRUSTEES. 1901 _All rights reserved._ LONDON: PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, STAMFORD STREET AND CHARING CROSS. PREFACE. One of the large north galleries approached from the Bird Gallery is devoted to the exhibition of the extensive Class of Mollusca. Specimens of the types of all the principal divisions of this Class are exhibited, either entire and preserved in spirit, or as models. However, as not the animals, but their shells have always been a favourite object of study, and a popular source of pleasure to collectors, the exhibition of the species of shells has been made as complete as the space of this Gallery admitted. It has thus proved adequate for the requirements of the majority of visitors and students who consult this Collection. A separate series of British Shells is exhibited in some small table-cases along the west wall. This Gallery also contains the exhibited series of Polyzoa, Brachiopoda, and Tunicata. The Starfish Gallery, so called from one of the best-known types of the Echinoderma, contains an exhibition of the animals of this Class, as well as of the somewhat heterogeneous assemblage of creatures which are comprised under the popular name of Worms (_Vermes_). These animals possess greater attraction to students of Natural History than to the general public, and many, from their small size or the soft nature of their body, are not suitable for exhibition. Therefore no attempt has been made to show more than a carefully selected number of the types of the larger groups. But the exhibition of very complete series, supplemented by models or figures, to illustrate the remarkable life history of some of these animals, also of specimens of the Worms which possess a special interest from their relation to man, render this Gallery particularly instructive to the student. This guide has been prepared by Mr. E. A. Smith, Mr. F. J. Bell, and Mr. R. Kirkpatrick, who have special charge of the collections described. In conclusion, thanks are due to Messrs. A. & C. Black, Messrs. F. Warne & Co., Messrs. Macmillan & Co., Crosby Lockwood & Son, and the Linnean Society for kindly allowing the use of _clichés_ from illustrations in various works published by them.