458 NEW YORK STATE MUSEUM 



To him my most sincere thanks are due. I am also under obligation to 



Mr Charles Schuchert, who kindly placed at my disposal the material 



collected by Messrs Walcott, Dale and Prindle during the prosecution of 



their work in the slate belt, and deposited now in the collection of the 



National Museum. Prof. R. P. Whitfield has kindly allowed me access to 



the Quebec graptolites of the Hall collection in the American Museum of 



Natural History ; and Mr Gilbert van Ingen of Princeton University has 



generously given me the benefit of his skill in photographing the obscure 



appendages of these organisms. 



Rudolf Ruedemann 



Assistant State Paleontologist 



