SUBSEQUENT MORAINAL LAKES. 451 



Probably the largest and deepest of the tributary morainal lakes was 

 the Rushford lake, in the Caneadea valley. The moraine which closed 

 the valle}^ is very massive, being one and one-half miles wide along the 

 river and reaching about four miles west, or up the Caneadea valley to 

 within about one mile of Rushford village. The material is mostly gravel 

 or karae drift, enclosing large kettles and one lake, " Moss pond." The 

 overflow was at the south edge of the moraine, and the creek has exca- 

 vated a winding channel, with several rock-cuts, along the south side of 

 the old valley. In the vicinity of Rushford, and between there and 

 Caneadea, the water planes are not conspicuous, it being an illustration 

 of the frequent comparative absence of static-water phenomena in locali- 

 ties where such water is positively known to have existed. 



There was no great difference in altitude between the levels of the 

 Rushford lake and the fourth-stage Genesee water, but it is probable that 

 the former was somewhat higher and that the Genesee waters never 

 flooded the Rushford valley. At the top of the rock-gorge the kame- 

 moraine dam is partially leveled as by stream floods. This plane has 

 been measured by aneroid on two separate occasions with results 1,533 

 and 1,548 feet altitude (see page 438). 



In the south branch of Caneadea valley still higher levels of an ante- 

 cedent local glacial lake will probably be found (see page 448). 



The morainal lake began when the ice-sheet uncovered the locality 

 and existed during a long period, sufficient to cut down through 200 feet 

 of Portage-Chemung shales ; it may have outlived the glacial waters in 

 the river basin. 



The Tuscarora morainal lake occupied the valley of the Kishawa creek 

 from some point north of Nunda village to the morainic dam, which still 

 blocks the junction of this valley w^ith the lower Canaseraga valley. The 

 rock-gorge has been referred to on page 429, and is familiar to travelers 

 on the Western New York and Pennsylvania railroad. In the old lake 

 basin the water-planes are very numerous and conspicuous, in that respect 

 being in striking contrast to the Rushford basin. The highest of the 

 Tuscarora levels are not much under the plane of Warren water which 

 buried the region. 



The Tuscarora lake did not come into existence until the Warren waters 

 were lowered, and it was probably the latest of the larger morainal lakes 

 in tributary streams. 



The Angelica lake was small but interesting, on account of the sim- 

 plicity of the evidence and the fact that the moraine dam has been eroded 

 until it is now far below the top of the rock-cut (see page 428). The 

 water-planes are clearly seen, one prominent terrace being the site of the 

 village, and a higher one forming a bench above the village. 



