12 NEW YORK STATE MUSEUM 



paleontologist accompanied by Dr Euedemann early in this- 

 season for the purpose of acquiring additional material, not only 

 of these crustaceans but also of the crdnoids of the overlying 

 layers, which formerly were obtained here in some quantity, but 

 of which our collection has too few examples. This exploitation 

 was quite successful and has added materially to the representa- 

 tion of these fossils in our possession. These Eurypterid crus- 

 taceans are creatures of singular structure and habit, and they 

 have not been studied with care since the description of the best 

 known species by Prof. Hall in 1859. The 10 intervening years 

 have brought many additions to our knowledge of these organ- 

 isms, and in other countries, specially Scotland, Sweden and Rus- 

 sia, they have been the basis of important investigations. It 

 would, I believe, be of great advantage to our science, if this 

 fauna as developed in the state of New York were restudied for 

 the incorporation of all recent additions to its morj)hology and 

 distribution. To make this to some extent practicable, I deem it 

 desirable to continue the exploitation of the Waterlimes in and 

 about the town of Litchfield, specially on the farm of Prof. C. F. 

 Wheelock at Jerusalem hill, by whose favor we have been per- 

 mitted to take material from farm walls and to open excavations 

 for this purpose. Mr Luther and Dr Ruedemann have spent a 

 few weeks in a continued search for these fossils with a most 

 satisfactory result. 



Last year I reported the acquisition of an important collection 

 of similar crustacean fossils from a lower geologic horizon, the 

 C. J. Sarle collection. This material is mostly new to science 

 and embodies much that is of interest. Mr Sarle's proposed 

 study of a part of this new crustacean fauna is not yet completed^ 

 but during the past season he has prosecuted some field investiga- 

 tions pertaining to the determination of its geologic position. 



Limestone lenses in Clinton and Niagara beds. In my last report 

 I recorded the fact that study was being made of certain peculiar 

 lenticular masses of limestone occurring in the upper beds of the 

 Clinton formation and in the Rochester shale. The problem 

 presented by these peculiar masses with their remarkable fossil 



