4 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



stratigraphy of that State. Dr. Eugene A. Smith, the first to decipher the correct 

 sequence of lower Tertiary formations in the Southern States, supplied important 

 collections from Alabama, particularly from the Midwayan group. 



Ample collections of washings with bryozoa from the typical Jacksonian of 

 Mississippi were secured by Mr. E. N. Lowe, State geologist, who has been ever 

 ready to obtain material to advance these studies. The lower Jacksonian fauna 

 herein described is largely the result of Mr. Lowe's efforts. Mr. John M. Nickles 

 also has contributed specimens for study, particularly from the Midwayan of 

 Arkansas. 



The Ulrich collection, now the property of the United States National Museum, 

 has furnished some excellent materials of great use in the present monograph. The 

 authors have also had the advantage of the advice and experience of Dr. E. O. 

 Ulrich, who made these particular collections in the hope that some day the subject 

 would be monographically treated. 



Professor H. Douville, member of the Institute of France, has verified our cla>-i- 

 fication, and he has been most generous to the senior author with his advice and en- 

 couragement. We are sincerely thankful for his help. 



The authors are deeply grateful to the National Academy of Sciences for 

 financial assistance which made it possible for them to prepare and include in this 

 monograph the important portion relating to the Cyclostomata, thereby completing 

 the study of the North American early Tertiary species. 



OBJECTS AND METHODS OF STUDY. 



There are many minute openings and almost imperceptible protuberances on 

 a fossil bryozoan. Their enumeration, the description of their form, size, and 

 position would be a work both tedious and perfectly useless, unless, by the aid 

 of zoology, a reason for their presence can be obtained. Here, more than anywhere 

 else, the intimate union of zoology with paleontology is absolutely necessarv. 



The fossil bryozoa are more than small perforated stones. They are the 

 remains of creatures of a former time, and the object of the paleontologist should 

 be their resurrection. His role is to animate them in order to classify them, and 

 to classify them correctly in order to use them. 



This fertile method of constant comparison with the living specimens is tending 

 to prevail in Europe, but here in America circumstances, notably the predominance 

 of the Paleozoic faunas, have not permitted its application in bryozoology. The 

 present authors have endeavored to inaugurate this method of research in America 

 by a study of the exuberant faunas of the great American Tertiary Gulf. They 

 have endeavored to describe these faunas so as to be understood by all naturalists 

 and not by the specialist alone. 



The lack of large monographs upon bryozoology causes the study of the fossil 

 forms to be exceptionally difficult. The most recent monograph, that of Hincks, 

 dates from 1880, and is concerned only with Great Britain. Since that time, it is 

 true, important researches have been made by many^ eminent naturalists of all 

 countries and published in a great number of scientific works, in all languages. 

 All these works are assembled only in the libraries of .the very few specialists who 



