THE 



NAUTILUS 



A MONTHLY JOURNAL 



DEVOTED TO THE INTERESTS OF 



CONCHOLOGISTS 



VOL. XXV. 

 MAY, 1911, to APRIL 1912. 



EDITORS AND PUBLISHERS : 

 U. A. Plummy, Curator of the Department of Mollusca, Academy ol Natural Scienct a 



PHILADELPHIA. 



C. W. JOHHSON, Curator of the Boston Society of Natural History, 



BOSTON. 



