NEW FOSSIL FRESH-WATER MOLLUSKS FROM 



ECUADOR 



By William B. Marshall 



Assistant Curator, Division of Mollusks, United States National Museum 



and 



Edgar O. Bowles 

 George Washington University, M'ashington, D. C. 



Specimens of fossil fresh-water mollusks recently received from 

 Dr. George Sheppard, Geologo del Estado, Republica del Ecuador, 

 yield three new genera, each represented bj'^ one new species, and a 

 new species of Pomacea. They were collected by Doctor Sheppard in 

 the vicinity of the towns of Biblian and Paccha, Ecuador. Until 

 recently both these towns were in the Province of Canar, in southern 

 Ecuador. A recent change in provincial boundaries leaves Biblian 

 in Canar but places Paccha in the adjoining province, Azuay. The 

 junior author has supplied the following data referring to the two 

 localities, which lie on the watershed between the Atlantic and the 

 Pacific : 



Biblian lies a few miles northeast of the provincial capital, 

 Azogues, and a little southeast of the city of Canar. It is located on 

 the northwest bank of a small river, tributary of the Rio Paute, the 

 waters of which, by way of the Rio Santiago and the Rio Maranon, 

 reach the Amazon in western Brazil. About 7 or 8 miles north, and 

 coming from some distance east, is a tributary of the Rio Canar, 

 which flows into the Rio Naranjal of the Pacific drainage. Between 

 the Naranjal and the Paute is a range of mountains, approximatel}^ 

 12,140 feet in altitude. Azogues, but a mile or two downstream from 

 Biblian, has an altitude of about 8,200 feet, indicating a rapidly 

 descending river, probably with high banks. 



Paccha, now in the Province of Azuay, is a much smaller town, 

 considerably south of Biblian and lying between the Rio Paute and 

 a tributarj^, the Rio Quingeo. It is situated in a high valley, sur- 

 rounded by hills, except on the side toward the Rio Paute, which 

 here flows in an east-northeast direction. Southwest, toward the Rio 

 Quingeo, is a high pass, but most of the surrounding country is less 

 than 10,830 feet in altitude. Cuenca, on the Rio Matadero, a western 



No. 2946.— Proceedings U. S. National Museum, Vol. 82, Art. 5 



139389—32 1 



