6 PHYLOGENY OF FUSUS AND ITS ALLIES. 



with Fitsiis. No new genera are here proposed for species eliminated 

 from Fitsiis, with few exceptions, though this will be necessary for a 

 large proportion of them. 



No researches in the phylogeny of invertebrates, as revealed by 

 the hard parts, can be carried on at the present time without a 

 recognition of the monumental work accomplished in this department 

 by the late lamented Professor Alpheus Hyatt. His researches have 

 paved the way for future investigators, and none can work in this 

 field without acknowledging themselves his pupils. The writer has 

 had the great good fortune to carry on a part of his investigations 

 under circumstances which admitted of ready discussion, with Pro- 

 fessor Hyatt, of many important points, and the cordial interest and 

 attention which Professor Hyatt gave to this work are among the 

 many pleasant memories associated with that best of teachers and 

 friends. In Professor R. T. Jackson, of Harvard University, the 

 writer has had a constant adviser, critic, and helpful sympathizer, and 

 his invaluable aid in these directions are gladly and freely acknowl- 

 edged. The writer is also indebted to Professor Jackson for assistance 

 in the supply of material for study, as well as for many other courtesies. 



The work, begun in 1898, was carried on in the Palaeontological 

 laboratory of Harvard University, and in various museums. Foremost 

 among the latter is the Museum of Comparative Zoology at Cambridge, 

 Mass.* The writer is greatly indebted to Dr. W. M. McWoodworth, 

 assistant in charge of the Museum, for permission to study the fine 

 series of Tertiary Fusidse especially from European localities, which 

 are contained in that museum, and which in extent and importance 

 are second to none in this country. To Dr. Walter Faxon, curator 

 of the department of recent mollusca, in the same museum, thanks and 

 acknowledgements are due, for opportunity to study the extensive 

 series of recent Fusidae under his charge, as well as for many courtesies 

 shown during the prosecution of the studies. The use of the collection 

 of the Boston Society of Natural History f was granted by Professor 

 Hyatt the curator. The writed spent two weeks in Washington, 

 studying the collections at the Smithsonian Institution, and he wishes 

 to make grateful acknowledgements of the numerous kindnesses shown 

 him by Dr. W. H. Dall, the curator of the department of molluscs, and 

 by the members of his staff. From Mr. Chas. T. Simpson and Dr. 

 T. W. Vaughan the writer received many courtesies and much as- 

 sistance. Through the kindness of Dr. Dall we have been enabled to 

 figure the protoconchs of Falsifiisus meyeri and Hcilprinia caloosacnsis. 



At the Johns Hopkins University in Baltimore, the writer was 

 given the opportunity to examine the Tertiary Fusoid shells in the 



1 



* Referred to as M. C. Z. in citation of localities, etc. 

 t Referred to as B. S. in the citation of localities, etc. 



( 



