94 THE NAUTILUS. 



lip was formed more than a half-whorl short of the original one. 

 The original parietal tooth is more than a half-whorl beyond the new 

 one. 



Polygyra infiecta Say. Cape Girardeau. 



Polygyra leporina Gld. Jackson. 



Polygyra monodon Rack. Jackson. See remarks under St. 

 Francois County. 



Polygyra fraterna imperforata Pils. Cape Girardeau. 



Polygyra hirsuta Say. Jackson and Allanville, the latter the 

 larger. 



Pyramidula alternata Say. Jackson and Allanville. 



Pyramidula perspectiva Say. Allanville and Jackson. 



Omphalina friahilis W. G. B. Cape Girardeau. Pilsbry and 

 Ferriss distinguish this species from fuliginosa largely by the ap- 

 pearance of the apical whorls, these being smooth, whitish-corneous 

 and unworn, while in southwestern /Mimosa the summit is invari- 

 ably worn, the cuticle removed from the earlier whorls. The shells 

 from Cape Girardeau are very fine, measuring 28 mm. diameter, and 

 the apex not worn in the least. 



Vitrea indentata Say. Allanville. 



Zonitoides arhoreus Say. Cape Girardeau and AUenville. 



Helicodiscus lineata Say. Allanville. 



Suecinea sp. Cape Girardeau. 



Physa gyrina Say. Allanville and Jackson. From a pond on 

 the west side of the Whitewater river at Allanville. The shells 

 were small ; from one on the east side a single larger one and of 

 short spire. 



Sphaermm soUdulum Prime. Jackson. 



MuscuHum elevntum Hald. Jackson. 



Miisculium transversum Say. Jackson. 



St. Genevieve, St. Genevieve County. 



Polygyra appressa Say. Found more abundantly than any other, 

 and more like those from central Missouri than others herein noted. 



Polygyra fraterna Say. 



Polygyra fraterna imperforata Pils. Of ten fraterna found six 

 were imperforate, and the others almost so. 



Polygyra inflecta Say. 



Pupoides marginata Say. 



