24 THE AMERICAN MONTHLY [Jan 



of tlie shells in it. The liviag forms in the lakes todaj 

 are the desceudauts of those. 



A Kettle-hole in Newark, N. J. 



The marsh is about 4,050 feet long and 900 feet broad 

 in the widest part. It narrows to a tongue which was 

 about 450 feet wide in the south west extremity. It point- 

 ed due northeast, which was the way the ice in the glacier 

 period came according to the opinions of most of the geo- 

 logists that have studied it in New Jersey. When I visited 

 the place, the temperature was 20° F. and the wind was 

 blowing sharply, but I saw men had been digging a ditch 

 through the marsh to lay a sewer. Subsequently, I found 

 they had laid a sewer through 1 1th street where they cut 

 through the marsh. The ditch was so deep that they had 

 gone through five feet of marsh material with the red 

 Newark sandstone below to the moraine. In the marsh 

 material, which was mostly fine sand, there was at the 

 bottom black peaty substance, the same as I got farther 

 north. Where they had cut the sewer through was about 

 one-third the distance down on the longitudinal of the 

 marsh. 



The sponge spicules were beautifully formed and plen- 

 tiful showing that the water in the marsh was still and 

 bhaliow, for sponges grown in plenty in such a piece of 

 water. The BacillariacesB were of the usual kinds: Na- 

 vicnla or the Pinnularia type, but scarce. The bog or 

 marsh was mostly made up of peat elastic and brown. 

 The sand at the north-eastern extremity and the Bacil- 

 laria at the south-western extremity showing that they, 

 being lightest, were carried to the south-western extrem- 

 ity, and the sand deposited at the south-eastern. It was 

 a kettle-hole and pointed the way the ice came. Kettle- 

 holes are not always filled with clay although they are 

 commonly supposed to be so. I was very much di.sap- 



