OF THE MOLLUSCA OF IOWA. 75 



Sphmrmm partumeium Say. Common, and even abun- 

 dant in many localities. 



tSjihcerium solidulum Prime. Des Moines, Iowa City, 

 and elsewhere. 



Sphcerium sulcatum Lamarck. Common, everywhere. 



SjphcBrium jayanum Prime. This species is found in 

 abundance in Kenneday's Lake near Des Moines, where 

 several hundred specimens of this hitherto rare form were 

 collected. 



Psidiiim abdiimn Hald. Common in the ponds and 

 streams of central Iowa. 



Family Unionid^. 



Anodonta corpulenta Cooper. Eastern Iowa : not com- 

 mon. Fine examples have been collected at Davenport, 

 and also in the Rock river in the northwestern part of the 

 state. 



Anodonta dmiielsii Lea. This species is entered here 

 upon the authority of Prof. R. E. Call who has reported 

 it from Fremont county. 



Anodonta decora Lea. Shells referable to this species 

 have been collected in various localities in eastern Iowa, 

 but it approaches so closely in some of its phases other 

 members of the grandis group that it is often almost im- 

 possible to separate the forms satisfactorily. 



Anodonta edentula Say. Generally distributed through- 

 out the state but nowhere very common. The Raccoon 

 river in Dallas county has afforded this species in greater 

 abundance than any other Iowa locality. 



Anodonta ferrussaciana Lea. Common ; especially in 

 the northern portion of the state. Mr. Grant has sui)plied 

 specimens from the Vermillion river at Parker, Turner 

 county, Dakota, which is the most northwesterly locality 

 yet reported for this species. 



