64 THE NAUTILUS. 
The localities at which shells were obtained, together with 
the species found at each, are listed below. 
From the concretionary horizon at the base of the pink loess 
and at the top of the underlying till; plant number 2 of the 
Mississippi Lime and Materials Co., Alton, Madison Co. 
Polygyra profunda pleistocenica Baker. 
Castoroides ohioensis Foster. Given to Dr. Leighton and said 
to have come from this horizon. Only a single incisor tooth 
(the left) was collected. 
The Polygyra was apparently very abundant at this horizon, 
seven pieces of concretions containing ten specimens of shells. 
The concretions are of lime which is very hard. Some of the 
shells are internal casts. 
From the lower ten feet of the pink loess, plant No. 2 Missis- 
sippi Lime and Materials Co., Alton. Many fragments of shells 
occurred, indicating an abundance of the different species at one 
time. 
Polygyra profunda pleistocenica Baker. A few specimens. 
Polygyra multilineata altonensis Baker. A few specimens. 
Polygyra hirsuta (Say). Rare. 
Gastrocopta armifera (Say). One specimen. 
From the upper part of the pink loess, plant No. 2 Missis- 
sippi Lime and Materials Co., Alton. 
Polygyra profunda pleistocenica Baker. A few specimens, 
Pyramidula alternata (Say). A few specimens. 
Circinaria concava (Say). One specimen. 
Succinea ovalis (Say). Several specimens. 
Helicina occulta Say. One specimen. 
From cliff of loess near corner Market and East 6th Street, 
Alton. From pink loess. 
Polygyra profunda pleistocenica Baker. Common. 
Polygyra multilineata alionensis Baker. One specimen. 
Polygyra appressa (Say). Common. 
Polygyra hirsuta (Say). Rare. 
Pyramidula alternata (Say). Not common. 
Helicodiscus paralellus (Say). One specimen. 
Circinaria concava (Say). One specimen. 
