PROCEEDINGS 



OP THE 



ACADEMY OF NATURAL SCIENCES 



OP 



PHILADELPHIA 



1865. 



January 3d. 

 Mr. Joseph Jeanes in the Chair. 







Thirteen members present. 



The following paper was presented for publication and referred to a 

 committee : 



" On extreme and exceptional variations of species of Diatomacese. 

 etc." By F. W. Lewis, M. D. 



January 10th. 

 The President, Dr. Bridges, in the Chair. 

 Twelve members present. 



January 17 th. 



The President, Dr. Bridges, in the Chair. 



Fifteen members present. 



The following paper was presented and referred to a committee : 

 " Eemarks on the genera Semicossyphus and Trochocopus." By Dr. 

 A. Giinther. 



January 24th. 

 The President, Dr. Bridges, in the Chair. 



Ten members present. 



The following paper was presented and referred to a committee : 



" Synopsis of the Strepomatidae, &c, Part IV." By George W. 

 Tryon, Jr. 



The Secretary announced the recent death of Dr. R. M. S. Jackson, 

 late a Correspondent of this Academy. 



1865.] 1 



