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MUSEUM OF COMPAr.ATIVE ZOOLOGY. 



319 



The same. Fourth Annual Ecport, 1840. The Hudson Hiver slate 

 group "is overlaid unconformably in many places by the various rock 

 formations of more recent origin." (p. 212.) The common and hydraulic 

 limestones at the base of the Hclderberg series "sometimes rest uncon- 

 fcirmably upon the Hudson slate group, as at Lawrence*s quarry, on the 

 Kondout, opposite AVilbur (see fig. G, copied from fig. 1, PI. 2G, Final 

 Eeport, 1843); sometimes conformably on the Shawangunk grit, .... 

 as at Rosentiale a,ud Lawrencevillc, on the Kondout-; sometimes on the 

 red and variegated sludes and grits that overlie tlie Sliawangunk grits, as 

 at the High Falls of the llondout in Marblctown." (p. 237.) Lawrence's 

 quarry is again mentioned (242) as affording "a fine exposure of the 

 different strata^, and tlie Hudson slates are seen unconformable, beloAV 

 the limestones." At Hasbrouck's quarries on Pino Mountain between 

 llondout and Kingston Point, tlie Hudson slate series dips 40-GO^ to 

 E. S. E. ; the overlying limestone and cement beds dip 80° W. N. W., 

 "and this dip continues nearly \miform along this line of upheave to the 

 *High Hocks' above Kingston Point." (p. 242.) 



The same. Fifth Annual Keport, 1841. There is " a line of fracture 

 and anticlinal axis" extending northward from New Jersey, passing 

 Kingston and the district here mapped. " On the west side of this axis 

 of fracture and elevation, the rocks dip to the westward at variable, bat 

 generally at sniall angles, while on the east side they dip at a high 

 angle to the eastward, and are frequently vertical in their stratification." 

 (p. G4.) Farther reference to Becraft's Mountain is made on page 1)0; 

 it is also said that west of the line of fracture "the superincumbent 

 rocks overlie this [Hudson slate] series conformably in most places." 

 The several lleldcrberg outliers known to Matlier are Bccraft's Moun- 

 tain and Mount Bob near Hudson; another in Grcenbush, between the 

 Sandlakc and Nassau roads, about two miles from Albany, first examined 

 by Dr. Eights ; and two others described by Eaton, one in the north 

 part of Grcenbush, five miles southeast of Troy, the other in the town 

 of Schaghticoke, on the north side of Tomhannock Creek (p. 87). 



The same. Geology of New York, First Distret, 1843. Most of 

 the observations arc repeated from the Annual Reports, pp. 330-373. 

 Bccraft's Mountain is described in detail (p. 351) and figured (PL 24, 

 fig. G, here copied, fig. 7) : no doubt is expressed of the unconformity 

 there ; but at Mount Bob (PL 38, fig. 1, here copied, fig. 8) it is said 

 to be "apparent." "Although the actual junction of the roeks of 

 the Hudson Kiver group with those of the Hclderberg division was 

 not observed between Kingston and Catt^kill, they were seen in many 



