466 GEOLOGICAL SURYEY OF NEW JERSEY. 
Var. radiosa, Grun. 
Fresh water. Camden: Ditches and meadow pools near 
Blackwood. 
. Kutzingiana (Thwaites?), Chauvin. 
Generally distributed along the coast—Lewis. 
. operculata, Kiitz. 
Fresh water. Common in ponds and ditches. Gloucester: 
Mullica Hill. Burlington: Marlton. Salem: Woodstown. 
Atlantic: Absecon. Camden: Kirkwood. Morris: Fossil at 
Drakesville. 
. rotula, Kiitz. 
Generally distributed along the coast—Lewis. 
. striata (Kiitz.), Grun. 
Salt or brackish water. Monmouth: Ditches near Shark 
River. Salem: Ditches near Salem Creek. Camden: Frequent 
in the water-supply of Camden. 
ACTINOCYCLUS, Bhrb. 
. Ralfsii, W. Sm. 
Marine. Monmouth: Occasional in marine mud of’ Shark 
River and Manasquan River. 
COSCINODISCUS, Ehrb. 
. eccentricus, Ehrb. 
Salt or brackish water. Occasional between tide marks and 
in marine mud. Monmouth: Manasquan River, Shark River ; 
fossil in Ocean Beach clay. Atlantic: Atlantic City, and Cape 
May. Camden: Rare in Camden water-supply. 
. lineatus, Ehrb. 
Salt or brackish water. Occasional in the same localities as 
the preceding species. 
nitidus, Greg. 
Marine. Monmouth: Occasional on the sand flats near the 
mouth of Manasquan River. 
