Pleistocene Ixipers at the Wfuhhigton Meetings. 231 
northwestern Ohio, and of Trenton limestone in northern New 
York, they are shown to have been formed after the departure of 
the hist ice-sheet, and are attriljuted to the postglacial rise of 
temperatnre and consequent expansion of the rocks. 
Another locality' of somewhat similar phenomena is at Lime 
Rock, close west of Caledonia and near the east line of LeRoy, 
Genesee county. N. Y. A great numljer of small anticlinal ridges 
there seen are postglacial, but they differ in type and probably in 
origin from the foregoing. They are mainly parallel with each 
other and with the strike of the gtrata. and the anticlinals are 
usually unsymmetric and much fractured. The surface rock is 
Corniferous limestone, underlain by Salina shales, in which a few 
miles northward the drill has discovered a bed of salt. Strongh' 
saline springs show that here salt and gypsum are being removed 
from the shales somewhat rapidly by underground drainage, and 
Mr. <Tilbert concludes that the overlying limestone sinks in large 
masses, and that the ridges are the superficial phenomena of the 
partings of these blocks. 
In the discussion of this paper. Prof. E. W. Claypole spoke 
of the irregular sinking of the surface in the salt mining district 
of Cheshire. England, whereby buildings and chimneys are 
caused to lean and fall if not rebuilt. 
Proc<!sxfs of moinitdin-hnildiny and fluur relationship to the 
favth'ti contraction. By Warren I>ham. The concluding part 
of this paper pointed out the evidences of unusual activity of 
the forces which produce folding of mountain ranges, eruption 
of lavas, and epirogenic uplifts and subsidences, during the 
Pleistocene period, in comparison with previous geologic time 
since the end of the Palaeozoic era. To this Pleistocene or Glacial 
period belong much plication and uplifting of the Coast range, of 
the 8t. Elias range, of the Sierra Nevada. AVahsatch, and other 
Basin ranges, and much of the grand outpouring of lavas from 
Lassen Peak and Mt. Shasta northward along the Cascade range 
and eastward to the Yellowstone National Park. 
In the ensuing discussion, Prof. Joseph LeConte referred to 
the proofs of great Pleistocene uplifts of North America, shown 
l>y river channels suljmerged by the sea to depths of 2.000 to 
3,000 feet on Ijoth the Atlantic and Pacific coasts. 
Ov the cranitif churartt rs of Eqnus e.rcelsns Leidy. By E. D. 
Cope. Exhibition of the skull of an extinct horse from the 
