PREFACE. 13 



Dr. J. C. Merriam, of the University of California, sent me all of the 

 Cretaceous and Tertiary materia] that he possessed from that State; and 

 Dr. T. W. Stanton, of the United States Gleolog-ical Survey, submitted to 

 me the Eocene corals collected by himself in California, and loaned me all 

 of the specimens in the United States National Museum from the Shark 

 River group of New Jersey. 



My own jjrivate collection, and that made by me for the United States 

 Geological Svu-vey, both of which are now the property of the United States 

 National Museum, were also available for study. 



Prof Alphonse Milne-Edwards, Director of the j\ruseum d'Histoire 

 Natm-elle of Paris, sent me, at the request of Mr. C. D. Walcott, Director 

 of the United States Geological Survey, photographs of Milne-Edwards 

 and Jules Haime's types of Astrohelia lesueuri, Oculina americana, and 

 Eiipsammia haleana, and Dr. H. S. Gane loaned me a specimen of TurhinoUa 

 acuticostata, which has the costse perfectly preserved. 



Besides the acknowledgments already made, I am indebted to Dr. W. H. 

 Dall, Mr. C. W. Johnson, Dr. R. T. Jackson, and Prof. Alpheus Hyatt for 

 other personal kindnesses. 



Dm-ing the summer of 1897 I went to Europe, for the puipose of 

 visiting various museums and studying collections of corals in order to make 

 comparisons with American material. While there I received courtesies 

 from Dr. W. Weltner, Gustos in the Museum ffir Naturkunde, Berlin; Dr. 

 N. Sokoh^w, of the Comite Geologique, in St. Petersburg; Prof. Th. Fuchs, 

 and his assistants, Drs. Wahner and Kittl, K.^ K. Hofmuseum, Vienna; 

 Professor Suess, of the University of Vienna; Gelieimrath Professor von 

 Zittel, in Munich; Professor Camei'ano, of the University of Turin; Messrs. 

 Bernard and Boule, of Muse'um d'Histoire Naturelle, Paris; Dr. Hemy 

 Woodward, Mr. A. Smith Woodward, Dr. J. W. Gregory, and 'Mr. R. B. 

 Newton, British Museum (Natural History); Messrs. L. L. Belinfante, 

 William Rupert Jones, and C. Davies Sherboni, of the Geological Society 

 of London, and Sir Archibald Geikie and Mr. E. T. Newton, of the Museum 

 of Practical Geology, London. To these gentlemen I express my heartiest 

 thanks for the aid that was rendered. 



Mr. Robert T. Hill submitted to me for study all of the material col- 

 lected by him during many years of exploration for Mr. Alexander Agassiz 

 in the West Indies. This material lias been of great interest for comparison. 



