viii PREFACE 



members, drawn chiefly from those included in the series men- 

 tioned. 



It was hoped that a list of the scientific communications pre- 

 sented to the Academy during the half century, some two thou- 

 sand in number, with references to the places of publications, 

 might be added to the volume, but it was found impossible in 

 the time available to compile the necessary data. The comple- 

 tion of this undertaking is therefore necessarily deferred until a 

 later date. 



ARNOLD HAOTTF.. 



