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kind was foiuul in any terrace within the limits of Monroe County. The 

 difference of opinion may be explained in part, by the fact that Mi'. Sie- 

 benthal has included the delta plains in his terraces and Professor Mars- 

 ters has omitted them, as is found later in liis paper. 



To turn to the terraces themselves, the most of them are capped with 

 ten or more feet of a mixture of clay and sand undoubtedly derived from 

 the disinte.sirated rocks constituting- the surface of the uplands. Some 

 of the other benches are capped with glacial material; others with both 

 glacial and residual material. Underneath the loose material are always 

 to be found friable sandstone, or more frequently sandy shales many feet 

 above the water in Bean Blossom Creek. The bench lying between Mt. 

 Tabor and Ellet's hill is composed of shale and shaly sandstone except 

 at the top. The sandstones and shales are exposed at several places along 

 the road leading east from Mt. Tabor as w'ell as in the ravines north 

 of the road. The top is capped hy a thin layer of sand or sandy clay. 

 The bench on Avhich Pleasant A'allty Church is situated is all shale except 

 the top part which is composed of a few feet of residual clay on which 

 rest ten feet of erratic gravel and clay. The bench on the north side 

 of Bean Blossom Creek, beginning almost one-half mile east of Bean 

 Blossom Church and extending to the Brown County line is coiuposed 

 of blue shale resting upon which are ten to twelve feet of residual clays. 



The benches seem to be due not to glacial agencies in the main, but 

 to the bench-weathering of the arenaceous shales of the region, together 

 with the formation of small side deltas which have become confluent. 

 This opinion is strengthened by the following facts: (1) The terraces are 

 higher above the creek bed at the east than at the west, when if tlu-y 

 had resulted from a laking of the basin as Mr. Siebenthal supposes they 

 were, they would have been higher at the west. (2) The material did not 

 come from tlie foot of the glacier in Brown County, as this author sup- 

 poses, because the finer material is along and just west of the Brown 

 County line, the coarser, farther down the creek. (3) While the benches 

 rise toward the east the deltas of the larger trilmtaries do not always do 

 so, thus leaving gaps that would have been tilled had the bench material 

 come doAvn the creek from the glacier which crossed its upper tributaries. 

 (4) The benches rise toward the east with the rise of the shales. 



In preglacial time Bean Blossom Creek, as we shall see later, cut its 

 channel to l)ase level. At that time all its tributaries likewise cut to grade. 

 Both the creek and its tributaries began to meander and to etch l)ack 



