THE NAUTILUS. 95 



that this digging is done not merely for locomotion — for he could do 

 it much easier — but in search of food. — Dr. V. Sterki. 



Some observations on how snails move their odontophores, may- 

 be of interest, and more should be done in this direction. Limnceidce 

 feeding on glass are easily observed, if not by the naked eye, then 

 with a good glass. In Planorhis the radnla is narrow, and is moved 

 from behind forward — as seen in quite a number of species. Physa 

 moves its wide, expanded radula from the sides toward the middle, 

 not forward. Limncea moves it forward, but not as decidedly as 

 Planorhis, and at the same time somewhat from the sides to the 

 middle. These different ways will be found to correspond with the 

 formation of the teeth in the different genera. — Dr. V. Sterki. 



EXCHANGES. 



Mr. a. W. Hanham will be glad to correspond with members of 

 the American Association of Conchologists with a view to exchang- 

 ing land and fresh-water shells. Address, Bank of British North 

 America, Quebec, Canada. 



Wanted — Zonites from any locality in exchange for British 

 Land and Fresh-water shells. — Robert Walton, Charles St., Lower 

 Roxborough, Philadelphia, Pa. 



Northwest Louisiana land and fresh- water shells for exchange. 

 Wanted, other shells. — T. Wayland Vcmghan, Mt. Lebanon, La. 



Anodonta suborbiculata Say. I have fine specimens of this 

 beautiful Anodonta, as well as many other Unionidce for exchange. 

 — W. S. Strode, M. D., Bernadotte, Illinois. 



Japanese Shells. A large variety of Marine, Fresh-Water and 

 Land Shells of Japan and of the Bahamas, my own collection, 

 printed list. — To exchange for species not now in my cabinet from 

 any part of the world; rare American Unionid?e, Strepomatid^e etc., 

 desired. — Frederick Stearns, Detroit, Michigan. 



OBITUARY. 



DR. JOHN CLARKSON JAY. 



Dr. John Clarkson Jay, a son of Peter Augustus Jay and grand- 

 son of Chief Justice John Jay, a distinguished member of the First 



