6 Trans. Acad. Sci. of St. Louis. 



globose, having a large aperture, a short, stumpy spire and 

 a very large body whorl; the umbilicus is open and deep. 



Animal: Not differing from the typical form. 



Radula and Jaw: Not examined. 



Distribution: Apparently the same as the typical form. 



Geological Distribution: Pleistocene. 



Habitat: Same as catascopium. 



Remarks: This distinct little variety has been found very 

 recently by Mr. F. M. Woodruff at Miller's, Indiana, in the 

 debris thrown up by the lake, where it may be collected 

 by thousands. Pinguis is distinguished by its very short 

 spire, swollen body whorl and large aperture. The specimens 

 from Miller's are all yellowish or corneous in color although 

 all the specimens from this locality were dead beach shells. 

 The surface is frequently strongly malleated. Thus far it has 

 been found only at Miller's, Indiana, on the Lake shore in 

 Chicago at Oak street, and at Edge water. 



3. Limnaea desidiosa Say. 



PI. I. f. 8. 



Limnaea desidiosa Say, Journ. Phil. Acad. 2 : 169. 1821. 



Limnaea modicella Say, Journ. Phil. Acad. 5 : 122. 1825. 



Limnaea acuta Lea, Trans. Amer. Phil. Soc. 5 : 114. pi. xix. f. 81. 1837. 



Limnaea philadtlphica Lea, Proc. Amer. Phil. Soc. 2 : 32. 1841. 



Limnaea plica Lea, Proc. Amer. Phil. Soc. 2 : 33. 1841. 



Limnaea rustica Lea, 1. c. p. 33. 1841. 



Limnaea planulati Lea, 1. c. p. 33. 1841. 



Limnaea jamesii Lea, Proc. Phil. Acad. 1864 : 113. 



Limnaea decampi L. H. Streng, The Nautilus. 9: 123. 1896. (Variety.?) 



/Shell: Subconic, pointed, oblong, rather thin, sometimes 

 inflated ; color light or dark horn ; surface shining, covered 

 with numerous crowded, fine lines of growth which can 

 scarcely be discerned on the apex ; whorls 5, somewhat shoul- 

 dered in some forms, the shoulder being near the suture; 

 the last whorl is very large, half the length of the entire 

 shell ; each whorl is double the size of the one preced- 



