43^ ^EW YORK STATE MUSEUM 



reservoir^ but above the pond thin, black, fine grained to coarse 

 grained, richly fossiliferous layers of Trenton limestone are again 

 exposed in the bed of the creek. The fossils Trinucleus 

 concentricus Eaton, Monticulipora (Prasopora) 

 lycoperdon Say and Rafinesquina alternata 

 (Con.) Hall and Clarke are specially abundant. These layers 

 belong to the very top of the Trenton substage and are typical of 

 it. Opposite the northwestern part of Rockton the rock again dis- 

 appears and is not exposed again till the Amsterdam water supply 

 pipe-line is reached. Along this line are loose pieces of rock which 

 were thrown out of the trench during the excavation and show 

 by their sharp angles that they were blasted from rock in place. 

 Near where the pipe-line crosses the Fulton-Montgomery county 

 line is a small exposure of very fine grained, dove limestone con- 

 taining bivalve Crustacea, and of slightly coarser grained similar 

 limestone containing corals (Streptelasma). This rock, there- 

 fore, belongs to the Birdseye and probably Black river substages. 

 Fragments of similar rock occur along the pipe-line to near the 

 branch of Chuctanunda creek northwest of Hagaman. Heavy 

 bedded arenaceous limestone is exposed in the bed of this creek. 

 Northwest of Hagaman and just north of the Fulton-Montgomery 

 county Une is a farm house standing well back from the road, and 

 known as the **01d Bunn place." The rock here is for the most 

 part typical Calciferous but some of the upper layers are of a rather 

 peculiar character. On fresh fracture they closely resemble Birds- 

 eye limestone, but the weathered surface shows knobs and reticula- 

 tions composed of arenaceous material weathered dull yellow. The 

 matrix weathers nearly white. Similar rock clearly referable by its 

 stratigraphic position in connection with its lithologic characters to 

 the fucoidal member of the Calciferous stage may be seen below the 

 quarry back of Crane's village,^ in the ledges along the West Shore 

 railroad opposite Crane's village and in the river bank below the 

 Amsterdam depot and at Pattersonville. 



Along the valley of the Chuctanunda between Sanford's mill and 

 Rockton are several fine exposures of the Trenton stage. In the 

 small gorge below the large pond east of Sanford's there is an 



^This place is called Cranesvllle on the U. S. geological survey Amsterdam topo- 

 graphic sheet but is known locally as Crane's village and is so on the N. Y. C. & 

 H. R. railroad time cards. 



