DEDICATION. 
7o His Excellency 
ROSWELL P. FLOWER, 
Governor of the State of New York: 
Sir: 
I have the honor to present to your Excellency a new volume of the Natural 
History of the State of New York, forming a continuation of the work on 
the Palaeontology of the State. 
This volume together with one other, already far advanced in its prepara¬ 
tion, will complete the work upon the revision of the genera of the 
Paleozoic Brachiopoda. The investigation, begun many years ago, and for a 
long time suspended, was resumed only in 1888, and while in the outset laboring 
under many disadvantages for want of adequate collections, the difficulties have 
been mainly overcome and the author is able to present the volume in a satis¬ 
factory form. The advance in our knowledge of this class of fossils during 
the past twenty-five years, and the later accumulation of material from various 
sources, for the illustration of the work, are the causes which have expanded 
the proposed Part ii of Volume IV of 1867 into two volumes, of which this is 
the first. The work has for its final object the bringing together, under one 
title, a summary and revision of all the genera of this class of fossils known 
in the rocks of New York and the adjacent States, to the Coal Measures 
inclusive. This will also serve as a revision of the genera and species already 
described in Volumes I to IV of the Palaeontology of New York, published 
during the interval from 1847 to 1867. 
The publication of the volume has been greatly delayed by causes beyond 
the control of the author, but the Act of the Legislature, Chapter 170 of the 
