This publication is issued four times a year, the first number in 

 each volume usually appearing in December. 



All exchanges should be addressed to the "Library of the Uni- 

 versity of Colorado, Boulder, Colo." 



Educational institutions, libraries, societies and individuals 

 desiring to be placed on the exchange list should make request to the 

 ** Secretary of the University of Colorado, Boulder, Colo.," to whom 

 also should be addressed any correspondence in regard to purchase 

 of single copies. 



