76 T. REPORT OF PROGRESS. K. W. CLAYPOLE. 



of fishes, which is usually recognized as the Catskill form- 

 ation. The stratigraphical geologist may be disposed to 



draw a hard line at the base of the red rocks and to say 

 that all above the line shall be Catskill, fossils included. 

 The palaeontologist may feel inclined to draw the line at 

 the highest shell-bearing bed and to say that all below 

 the line shall be Chemung, red sandstone and shale in- 

 cluded. But neither is a logical sequence from the facts. 

 Passage beds must be expected between all the great forma- 

 tions. The day is near when all the hard lines hitherto 

 drawn across the geological column will be blurred, and 

 system will shade into system as gently as the colors of the 

 rainbow fade into one another. Passage beds even now con- 

 nect many groups once considered distinct, and the great 

 breaks in life formerly taken to prove total destruction, and 

 recreation of species now only imply migration and immi- 

 gration caused by secular geographical changes. 



This is the view adopted in the following reports. The 

 stratigraphy and palaeontology of these shales and sand- 

 stones are taken to indicate changes of level and margin in 

 the palaeozoic ocean, causing local destruction or migration 

 of the animal j)opulation, which returned whenever condi- 

 tions had become re-adapted to it, or it had adapted itself 

 to them.* 



The King's Mill sandstone itself affords evidence of 

 changes of this nature. It indicates beyond question shal- 

 low water. The shell-casts so abundant in it at King s Mill 

 and other places are nearly all dead and drifted shells. I 

 have seen few specimens in this bed having the two valves 

 in place. They were evidently heaped up by the waves in 

 massfs. thinning off in every direction just as dead shells 

 are now driven and massed together on a beach. Whether 

 this shallow water really indicates a beach at King's Mill, 

 near the commencement of the Catskill area, or a sand bank 

 <>ut mi sea, cannot be determined by investigations within the 

 narrow Limits of a single county. 



On the other hand the.fossils found in the shales 500 feet 

 above the King*s Mill sandstone indicate that the animals 



♦These passage beds are colored with the Catskill group on the map. 



