THE NAUTILUS. 63 
that the pink loess, believed to be of Sangamon age, is the rich- 
est in number of syecies, ana that the characteristic post-lowan 
(Peorian) fossil, Pyramidula shimekii occurs only in the buff 
loess. Whether this distribution is to be considered as apply- 
ing to the whole body of the loesses of this area, or is simply 
the result of local collecting, cannot be known until more ex- 
tensive collections are made. The collections made by Dr. 
Leighton are from several localities in both Madison and St. 
Clair counties and also from different levels in the deposits, and 
these are believed to represent fairly well the general distribu- 
tion of the loess faunas of this region. It is probable that a 
larger number of the minute species could be found as a result 
of prolonged search carried on especially forthem. The mater- 
ial has been placed in the University of Illinois Museum through 
the courtesy of the Illinois Geological Survey. They are num- 
bered P 738 to P 764 of the collection of Palaeontology. 
TABLE OF DISTRIBUTION OF LIFE IN LOESSES NEAR ALTON. 
Concretionary horizon. Polygyra profunda pleistocenica. 
(Above underlying till, be- Castoroides ohioensis (incisor 
lieved to be Kansan. ) tooth). 
Mammut americanum (Kerr). 
(Reported by Worthen. ) 
Yarmouth interval. 
Pink loess believed to be of Polygyra profunda pleistocenica. 
Sangamon age. Polygyra multilineata altonensis. 
Polygyra hirsuta. 
Polygyra appressa. 
Pyramidula alternata. 
Helicodiscus paralellus. 
Gastrocopta armifera. 
Zonitoides arborea. 
Upper part of loess. Circinaria concava. 
Succinea ovalis. 
Helicina occulta. 
Buff loess. 
Karly Peorian interval. Pyramidula shimekii. 
Succinea ovalis. 
