298 NEW YORK STATE MUSEUM 



in the grit, from which he obtained a few very evident segments 

 of Eurypteruslike merostomes. 



The discovery of such fossils in eastern New York, long looked 

 for but never before found, and their evident importance in the 

 correlation of the sediments, rendered it desirable that these beds 

 should.be extensively exploited. 



This work of collecting has been carried out successfully by 

 Mr H. C. Wardell and the material on which the following account 

 of the stratigraphy of the fossils is based is quite extensive. 



The present line of the Erie Railroad from Otisville west for a. 

 distance of a mile or two passes over the steep grade of the 

 Shawangunk mountain. Extensive operations are now under way 

 to reduce this grade by a tunnel directly through the mountain. 

 The present railroad cut at the summit of the hill transects inclined 

 layers of the Shawangunk grit and above this cut at the east lies 

 the long quarry face from which the crustacean remains were 

 first obtained. This rock face has been torn into extensively in 

 the removal of rock which is crushed and used for ballast. 



The stratigraphy along this section is as follows : About 

 54 niile west of Otisville along the railroad are " Hudson River " 

 shales standing at an inclination of about 45 ° w. Westward the 

 eroded edges of these shales are abruptly overlain by the con- 

 glomerate basal layers of the Shawangunk grit series, the Green 

 Pond conglomerate of Darton and the New Jersey geologists, 

 which in the expansion of the formation in the Kittatinny mountain 

 attains a much greater thickness than here. In the railroad cut 

 these conglomerate layers attain a thickness of about 50 feet but 

 pass gradually into the finer typical grit above. The thickness that 

 may be ascribed to the grit here is 450 feet and it again passes 

 upward into looser sandstones. 



One half mile south of this section along the Erie Railroad the 

 beds referable to the Shawangunk series attain a thickness of 

 approximately 550 feet. From the base of the series at the con- 

 tact with the Lorraine shales through a section 350 feet are 

 innumerable thin layers of black shale. Above this the thin shale 

 layers become gray and more argillaceous but continue to carry 

 the merostome fauna with the addition of some singular phyllo- 

 carids whose structure has not yet been completely made out. 



Mr Wardell has measured this section in detail and the full 

 statement of it is very interesting as showing the remarkable con- 

 tinuation of these alternations of black shale bands through the 

 arenaceous deposits. 



