INTRODUCTION TO PART III. (_Ctenostomata_ and _Phylactolæmata_) 163 Status and Structure of the Polyzoa 163 Capture and Digestion of Food: Elimination of Waste Products 166 Reproduction: Budding 168 Development 170 Movements 172 Distribution of the Freshwater Polyzoa 173 Polyzoa of Brackish Water 174 History of the Study of Freshwater Polyzoa 177 Bibliography of the Freshwater Polyzoa 178 GLOSSARY OF TECHNICAL TERMS USED IN PART III. 181 SYNOPSIS OF THE CLASSIFICATION OF THE POLYZOA 183 SYNOPSIS OF THE SUBCLASSES, ORDERS, AND SUBORDERS 183 SYNOPSIS OF THE LEADING CHARACTERS OF THE DIVISIONS OF THE SUBORDER CTENOSTOMATA 185 SYSTEMATIC LIST OF THE INDIAN FRESHWATER POLYZOA 187 APPENDIX TO THE VOLUME 239 Hints on the Preparation of Specimens 239 ADDENDA 242 Part I. 242 Part II. 245 Part III. 245 ALPHABETICAL INDEX 249 EXPLANATION OF PLATES. EDITOR'S PREFACE. Dr. N. Annandale's volume on the Freshwater SPONGES, POLYZOA, and HYDRIDA contains an account of three of the chief groups of freshwater organisms. Although he deals mainly with Indian forms the book contains an unusually full account of the life-history and bionomics of freshwater Sponges, Polyzoa, and Hydrozoa. I have to thank Dr. Annandale for the great care he has taken in the preparation of his manuscript for the press, and also the Trustees of the Indian Museum, Calcutta, for their kindness in placing material at the disposal of the Author. A. E. SHIPLEY. Christ's College, Cambridge, March 1911. SYSTEMATIC INDEX. Page PORIFERA. Order HALICHONDRINA 65 Fam. 1. SPONGILLIDÆ 65