156 MEMOIRS OF THE CARNEGIE MUSEUM. 



Localities in Pennsylvania represented in the Carnegie Museum: 



Dcla ware-dra in age : 

 Delaware River, Peun's Manor, Bucks Co. (young, approachinjji; tri/oni). 

 White Clay Creek, Avondale, Chester Co. (typical creek-form). 

 Crum Creek, Delaware Co. (Hartman collection) (creek-form, but thin). 

 Sphuylkill Canal, Manayunk, Philadelphia Co. (tliin-shelled creek-form). 



Schuylkill River, Philadelphia (Hartman collection) (labeled tryoni, and representing this type). 

 Wissahickon Creek, Roxboro, Philadelphia Co. (creek-form). 

 Little Neshaminy Creek, Grenoble, Bucks Co. (creek-form). 

 In a dry pond of Mahoning Creek, Lehighton, Carbon Co. (pond-form). 

 Echo Lake, Monroe Co. (G. H. Clapp, donor). 



Susqueha n na-drn inage: ^^^ 

 Conewago Creek, York Haven, York Co. (creek-form). 

 Penn Canal, Selinsgrove, Snyder Co. (lake-form). 



Chemung River, South Waverly, Bradford Co. (creek-form, remarkaljly light green, found in riffles). 

 Mill-race of Crooked Creek, Tioga, Tioga Co. (typical creek-form). 

 Ponds near paper-mill, Lockhaven, Clinton Co. (all typical pond-form). 

 Beaver Dam Creek, Flinton, Cambria Co. (D. A. Atkinson) (typical pond-form: from an old dam in 



the creek; some of the younger ones incline toward the creek-form). 



Potomac-drai)iage: 

 Conococheague Creek, Greencastle, Franklin Co. (creek-form, unusually thick-shelled; from riffles in 



water heavily charged with lime); Scotland, Franklin Co. (creek-form, dwarfed). 

 Great Tonoloway Creek, Thompson Township, Fulton Co. (creek-form). 



Localities in Pennsylvania represented in the Philadelphia Academy of Natural 

 Sciences: 



East wicks Park, Grays Ferry, Philadelphia (S. R. Roberts). 



Wister Dam, Germantown, Pliiladelphia Co. (W. Stone). 



Oxford Dam, Guinea Creek,"^ Woodbourne, Bucks Co. (H. W. Fowler). 



Porters Lake, Pike Co. (S. N. Rhoads) (headwaters of Bushkill Creek, to Delaware). 



Harvey Lake, Luzerne Co. (C. H. Conner) (W. Stone) (Harvey Creek, to North Branch Suscjuehanna). 



On New Jersey side of Delaware: 

 Pond near Delaware River, Delanco, Burlington Co., New Jersey (H. A. Pilsbrj'). 



Other localities in the Carnegie Museum: 



Monmouth, Kennebec Co., Maine (Woods collection) (typical creek-form). 



Charles River, Cambridge, Middlesex Co., Massachusetts (Mrs. L. D. Thompson) (creek-form). 



Lake Ontario, Braddock Bay, Manitou Beach, Monroe Co., New York (R. H. Santens)."" 



'" A dead and broken shell was seen, but not taken, in the Juniata River (Raystown Branch) at 

 Ardenheim, Huntingdon Co. 



■" No such name is on the topograpliical map; the creek at Woodbourne is a branch of Mill Creek. 



■"'One specimen, collected together with specimens of A. grandis footiana, mentioned above. It 

 has the typical shape of the creek-form of A. cataracta, and differs from the others in the beaks, which 

 arc not inflated. Beak-sculpture jioorly preserved, but apparently of the cataracta-type. 



