THE NAUTILUS. 131 



I have in my collection specimens from sixteen counties in Mis- 

 souri, and these vary greatly in size from 18 mm. to '62 mm. diam- 

 eter. The largest is from Scott county in southwest Missouri ; Irom 

 Galena, Stone county they vary from 26 to 30 mm.; from Boone 

 county from 23 to 30 mm.; and from Kansas City 18 to 27 mm. 



The specimens from Kansas City are interesting, and the average 

 size at two points within the City dilfeis quite markedly. From an 

 old cemetery near Main and 27th streets I collected more than 

 ninety living shells, and from the bluffs about the Union Station I 

 found eight dead shells ; ths following table will show the sizes from 

 tlie two places : 



Diameter, Mm. Cemetery. Bluffs. 



18 2 

 18.5 2 



19 11 

 19.5 7 



20 20 1 

 20.5 8 



21 16 

 21.5 6 



22 7 

 22.5 5 



23 5 1 

 23.5 1 2 



24 1 1 

 24.5 1 



25 1 1 

 27 1 



At Boonville I found one dead but fresh shell of Polygym mnltt'H- 

 ne"tn Say, the only one 1 have found in the State. Tlie Polyjyra 

 divexta Ghl., is found living in the southern counties of the Suite, 

 and I liave it from the Postpliocene at St. Joseph. From the Post- 

 pliocene of Boone and Moniteau <'Ounties I have the Polygyra pro- 

 /uiufa Say, but have not found it living in the State. To the 

 Nautilus for June 1894, I noticed finding Polygyra andrexcsce W. 

 G. B. in St. Francois county. I have P. pennsylvauica from St. 

 Louis county, and I'rom the Postpliocene of Boone county. 



