PREFACE. 7 



paration of the descriptions. The excellent photographs, also, 

 illustrating 1 these Bryozoa were prepared by Dr. Bassler or under 

 his immediate supervision. For the preparation of descriptions 

 and illustrations of the new species of Echinoids, I am under 

 obligation to Dr. W. B. Clark. The crinoidal element in the 

 faunas studied is meager, a single new form having been ob- 

 served, but for suggestions as to the relationship of this form 

 I am indebted to Dr. Frank Springer. To Mr. J. M. Manley, 

 of New Brunswick, I am indebted for the specimens of Corbula 

 manleyi from the Raritan formation; invertebrate remains are 

 exceedingly unusual in this formation, and Mr. Manley deserves 

 great credit as a collector for discovering this form. Also to 

 Mr. G. N. Knapp, I wish to express my obligation. Mr. Knapp's 

 wonderfully "detailed knowledge of the Cretaceous formations 

 of New Jersey has been of inestimable value to me during the 

 prosecution of the field work, in assisting me to find the best 

 fossil localities without loss of time. To Dr. H. B. Kiimmel, 

 the State Geologist, I am under lasting obligations for the con- 

 tinued interest he has shown in the work, and for the encourage- 

 ment he has continually given during its prosecution. 

 Chicago, Dec. ist, 1906. 



