IMPORTANT. 



By resolution of the Council of the New York Academy of 

 Sciences, the committee on library was authorized to remove from 

 the Exchange List the names of libraries and institutions that 

 issue no scientific publications ; and to add to the list the names 

 of one hundred societies that issue scientific papers. 



In accordance with the above mentioned resolution institutions 

 so dropped from the free list will cease to receive the future pub- 

 lications of the New York Academy of Sciences after the issue of 

 Volume X. of the Annals. The series known as Transactions was 

 discontinued with the issue of Yolume XYI (1898). 



A revised list of exchanges will soon be printed and sent to all 

 on the present exchange list. Libraries and other institutions 

 whose names do not appear on the revised list may then become 

 subscribers to the new series of the Annals by payment of the 

 fixed price of threG ($3.00) dollars a volume. 



Beginning with Yol. XL each volume of the Annals will coin- 

 cide with a calendar year and will be issued in three parts. 



Subscriptions and communications should be addressed to the 

 Editor of the Annals. 



Gilbert van Ingen, 



Columbia University, 

 West 116th Street, 

 New York City. 



