iv DEDICATION. 



Genera. Of this number ninety-seven are Trilobites, which have perhaps a 

 greater general interesl than any other class of fossils. 



I he material furnishing these descriptions and illustrations is chiefly the 

 result of field collections made within the State of New York; some of the 

 specimens dating hack as far as the year 1832; including also specimens from 

 the collections of private individuals, and from the cabinets of institutions of 

 learning, which have been placed at the disposal of the author for the purpose 

 of enriching this volume. 



While the work is far from reaching that degree of completeness which the 

 author could desire, it must be regarded as the best which could be accom- 

 plished under existing circumstances; presenting, as it does, a systematic 

 arrangemenl of the material at our disposal, it will furnish to students and 

 teachers the means of study, and classification of their own collections, and in 

 this view the author will hope that it may not prove unworthy of a place 

 among the series of volumes intended to illustrate the Natural History of the 

 Statk of New York. 



I have the honor to be, 



With great respect, 



Your obedient Servant, 



JAMES HALL, 



Albany, March, 1888. 



State Geologist and Paleontologist. 



