1905.J 
NATURAL SCIENCES OF PHILADELPHIA. 
917 
Other than through the Hayden Medal the award of which is re- 
stricted both in frequency and field of application, election to corres- 
ponding membership is the only dignified means at the disposal of the 
Academy by which its recognition of scientific eminence can be ex- 
pressed. It is a most important function of well-established scientific 
institutions to seek out students who have made discoveries of excep- 
tional merit and to honor and encourage them. But the value of such 
approval is measured by the care and discrimination with which it is 
given. If placed indiscriminately upon work of both great and small 
worth it soon becomes cheapened and degraded to the lower level; but 
if a high standard be continuously maintained both the giver and the 
recipient of the honor gain in dignity. In awarding the correspond- 
ent’s diploma it seems most important that the Academy should keep 
these principles ever in view, and in no case permit its standard of 
excellence to be lowered. 
During the past year Charles D. Walcott, George T. Moore, John 
Sterling Kingsley and Harry Fielding Reid were elected correspond- 
ents and the first named was awarded the Hayden Medal in gold. 
The deaths during the year of the following correspondents were 
announced from the chair: Alpheus Spring Packard, Alfred Preud- 
homme de Borre, Henri di Saussure, Victor Raulin, Baron Ferdinand 
von Richthofen, and Albert von Koelliker. 
Eight notices of the death of prominent scientific men were received 
and acknowledged on behalf of the Academy by suitable letters of 
sympathy. Congratulatory letters were forwarded to the Entomo- 
logical Society of Belgium and the Natural History Society of Schles- 
wig-Holstein upon the occasions of the celebration of the fiftieth anni- 
versary of their founding; and to the University of Illinois upon the 
installation of President Edmund James. From the Sullivant Moss 
Chapter and the Pennsylvania Society for the Prevention of Tuber- 
culosis were received letters thanking the Academy for the use of rooms 
in which their meetings were held. Letters of appreciation and thanks 
for courtesies extended to them were also received from several of 
the scientific societies which met in Philadelphia during Convocation 
Week of 1904. 
Invitations to the Academy to send delegates were received from 
the Presidential Installation Committee of the University of Illinois 
and from three international congresses of learning. The interest of 
the Academy in the proceedings and its regret at being unable to send 
delegates were in each case expressed in due form. 
Various letters requesting information, the loan of specimens, or 
