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NEW YORK STATE MUSEUM 



some thinner, rusty, decomposed layers in which fragments of 

 trilobites and brachiopods are very abundant. The trilobite 

 fragments are smaller than those displayed on the slab described 

 above, but in other respects are quite similar. They were identified 

 as fragments of Olenellus, probably t h o m p s o n i. The 

 brachiopods bear a strong resemblance to Obolella. Two speci- 

 mens of the rusty quartzite crowded with fossils are shown in 

 figure 15. 



Fig. 15 Fossiliferous Lower Cambric quartzite 



In the summer of 1908 the opercula of H y o 1 i t h e 1 1 u s 

 micans were discovered in the limestone overlying the compact 

 quartzite in Ladue's orchard at an estimated distance of 20 feet 

 above the latter. After a careful search another operculum was 

 found at a slightly higher level in the first ledge east of the lower 

 barn on Jones's farm. 



Age and correlation. These fossils prove the quartzite to be 

 of Lower Cambric age. The similar relations which it has to the 

 underlying gneiss indicate that it is the equivalent of the basal 

 quartzite at Poughquag. The latter was described and named by 

 Prof. J. D. Dana^ as the Poughquag quartzite. 



1 Amer. Jour. Sci., Ser. 3, 1872, 3 :25o-56. 



