168 TWENTIETH ANNUAL REPORT OF THE REGENTS. 



The author, both in the preface and the body of the volume, has made 

 acknowledgments to many gentlemen for their liberality in furnishing 

 specimens for study and illustration during the progress of the work. 

 Among those specially named are Dr. G. A. Williams, of Boonville, 

 Mo.; Dr. James Knapp, of Louisville, Ky. ; Dr. C. R(EMinger, of 

 Ann- Arbor, Michigan; Major S. S. Lyon, of Jeffersonville, Indiana; 

 Mr. 0. St. John, of Waterloo, Iowa; Col. E. Jewett, of Utica, New- 

 York; Joseph Sulltvant, Esq., of Columbus, Ohio; the late Dr. 

 Mann, of Milford, Ohio; Prof. Wright, of Hamilton, and J. DeCew, 

 Esq., of Cayuga, Canada West. 



A special tribute is paid to the late Ledyard Lincklaen, Esq., of 

 Cazenovia, with whom the author enjoyed an uninterrupted friendship of 

 many years, and who at all times liberally aided the progress of geological 

 investigation, and contributed to the State Museum and the Natural 

 History publications of the State. 



The drawings illustrating the species have all been made by Mr. R. P. 

 Whitfield and lithographed by Mr. F. J. Swinton, and the proof sheets 

 have been revised by Mr. John Paterson. 



ERRATA, 



On page 146, Orthis idas should be changed to 0. cryna. 



" " 147, Stophodonta textilis, page 108 of volume, is a synonym, and will be 

 changed to S. junia in the explanation of plates. 



*' " 159; the Ccelospira referred to C. concava, has, on further examination, 

 proved a distinct species, and will be indicated as C. Camilla in the 

 explanation of plates. 



" " 165 Cryptonella ? lincklceni has proved to be a true Terebratula, 



