92 Natural History Bulletin. 



mens from Benton county, Iowa. The species now occurs 

 throughout the eastern United States. 



Mesodon albolabris, (Say) Morse. Two specimens were 

 collected in Sarpy county, Nebraska. These are like average 

 recent shells from Minnesota and Iowa, but smaller than eas- 

 tern specimens. The species now ranges from Canada to 

 Arkansas. 



Mesodon profunda, (Say) Binn. Specimens were collected 

 in Sarpy and Douglas counties, Nebraska, and Pottawatta- 

 mie county, Iowa. They are like medium and small recent 

 shells from Iowa. The species now occurs from Minnesota to 

 Virgmia. 



Strobila labyrinthica, (Say) Morse. Only two specimens 

 were collected in Pottawattamie county, Iowa. These are 

 precisely like the recent specimens from Texas, but smaller 

 than Iowa and Minnesota shells. It ranges now throughout 

 the eastern portion of the continent. 



Pti-pa fallax, Say. Specimens were taken in Fremont 

 county, Iowa. These are like Ohio and Iowa recent shells. 

 The species occurs from New England to Texas. 



Pupa contracta, Sa}'. But one specimen was taken in Pot- 

 tawattamie count}', Iowa. It is above the average in size, 

 resembling large Iowa and Nebraska specimens. The species 

 is now found throughout the eastern part of the continent. 



According to their distribution these new species may be 

 arranijed as follows: 



Mesodon profunda should be added to the list at the bottom 

 of p. 2IO in the former article, while the remaining species 

 should be added to the Hst immediately preceding it. As to 

 habitat Pupa contracta should be listed with Z. arboretts, Z. 

 minusculns, etc., on p. 213 of the former article. The remain- 

 ing species prefer damp, wooded places in the vicinity of 

 streams. The presence of these latter shells in such small 

 numbers would not interfere with our conception of the nature 



