DESCRIPTIONS 



FOSSIL CORALS FROM THE NIAGARA AND UPPER HEL- 

 DERBERG GROUPS. 



The fossil corals of the museum collections have been accumulating 

 for many years, but there has been little opportunity of giving special 

 systematic attention to their study. In 1876 some forty plates of photo- 

 graphic illustrations of species occurring in the Upper Helderberg and 

 Hamilton groups were published. In the meantime large collections have 

 been made from these rocks, and in 1877 the writer purchased of 

 Rev. H. Herzer, now of Berea, Ohio, an extensive collection made from 

 the several formations of Ohio, Indiana, Kentucky, Tennessee, Canada 

 West and New York. This collection is especially rich in corals, 

 from the Falls of the Ohio and adjacent country, and the speci- 

 mens have been prepared with great care and labor to show the 

 structure. The organic body being in a silicified condition has per- 

 mitted the use of acids for the removal of the matrix and the filling 

 of the cells. In this manner, through the labor of Mr. Herzer, a very 

 remarkable collection had been formed. Later on Dr. James Knapp 

 and Henry Nettleroth Esq., of Louisville have contributed many 

 specimens from the Falls of Ohio and the vicinity of Louisville which 

 have increased the value and interest of the former collection. 



Mr. C. D. Walcott, now of the United States Geological Survey, has 

 made, for the State Museum, very extensive collections of corals from 

 the Upper Helderberg limestone of Western New York and Canada 

 West; and from Eastern New York, collections have been made by 

 Dr. J. W. Hall and others. The writer has likewise employed Mr. John 

 De Cew, of Cayuga, Ontario, in collecting the corals of that part of the 

 country and he has purchased a collection of these fossils from Mr. Ed- 

 mond De Cew, of the same place. These collections altogether, have 

 furnished a considerable amount of new material for study and descrip- 

 tion. 



Nearly all the species heretofore described by MM. Edwards and 

 Haime, Mr. Billings, and Dr. Rominger have been recognized in these 



