rBBBUAEY 21, 1913] 



SCIENCE 



295 



eial and marine watera that lay against its 

 receding border. The local lakes in the 

 side valleys of the Hudson depression and 

 about the Adirondack highland are not 

 indicated ; and the ice border is more or less 

 generalized. The latter is located defi- 

 nitely along the lines of the ice-border 

 drainage. 



lowed up the Hudson Valley, finally reach- 

 ing the Champlain basin and eventually 

 uniting with the oceanic waters of the St. 

 Lawrence Gulf. The Hudson inlet thus be- 

 came the Hudson-Champlain inlet and 

 finally the Hudson-Champlain strait, con- 

 necting New York Bay with the Champlain 

 Sea. When the ice front backed away 



GLACIAL LAKES OP NEW YORK STATE 



The accompanying chart shows the time 

 relationship of the waters in the several 

 basins of the state. The vertical spacing is 

 only suggestive of the succession of the 

 waters and their geographic relations, and 

 has little significance as to the duration of 

 the episodes. 



MARINE WATERS 



During the waning of the latest ice sheet 

 the Hudson-Champlain Valley and the St. 

 Lawrence and Ontario basins were beneath 

 the level of the ocean. As the ice front re- 

 ceded northward the sea-level waters fol- 



from the Covey Hill promontory the gla- 

 cial waters of the Ontario basin, the Sec- 

 ond Iroquois, fell to and became confluent 

 with the sea-level waters. The highest 

 plane of the sea-level waters in the Ontario 

 basin is relatively weak and has not been 

 fully determined, but an inferior level of 

 long persistence showing heavy bar con- 

 struction has been mapped and named 

 Gilbert Gulf. This stage, which includes 

 the series of strong bars at Covey Hill post- 

 office, is depicted in map number 16. 

 On the parallel of New York City it ap- 



