QUARRYING FOSSIL SEA URCHINS 



By JAMES H. BENN 

 Scientific Aid, Department of Geology, U. S. National Museum 



In July 1939 Dr. William F. Foshag of the Museum staff, while 

 upon vacation at Scientists Cliffs, Port Republic, Md., came upon 

 some curious fragmentary calcareous plates lying at the foot of a 

 bluff overlooking Chesapeake Bay. Investigating further, he found 

 someone had been digging in the loose, unconsolidated sand and clay 

 some 18 or 20 feet above the beach, from whence the fragments had 

 been dislodged. Proceeding then to do some prospecting of his own 

 in these abandoned diggings, he soon began to uncover what ap- 

 peared to be a rich deposit of beautifully preserved fossil sea urchins 

 (echinoids). Collecting a fine representative group of specimens, he 

 returned to Washington and submitted them to the proper Museum 

 authorities. Soon thereafter I received a detail to proceed to this 

 locality and obtain a large group for the Museum exhibits. 



Arriving at the cliffs on July 17, I joined Drs. Foshag, Kellogg, 

 Resser, and Cooper, all of the National Museum staff, who were 

 studying the locality from various standpoints. 



Mr. Gravett, owner of Scientists Cliffs, assigned me a site for my 

 camp, which was soon in order ; in company with Drs. Foshag and 

 Kellogg, I then proceeded to investigate the deposit which lay less than 

 a mile north along the beach from Scientists Cliffs and from 18 to 

 20 feet up in the bluffs on the western shore of Chesapeake Bay. 



The sea urchins lay imbedded in a loose, uncemented sand in com- 

 pany with a fair number of barnacles and an occasional sand dollar. 

 The thickness of the layer of fossils was no greater than 8 inches 

 and in places much less. The width was approximately 3^ feet. The 

 axis of the deposit was at a northwest variance with north-south 

 trend of the bluff, the fossil bed appearing at the southerly apex of 

 the angle thus formed and disappearing northwesterly into the bluff. 

 Dr. Foshag had cut away a space in the bluff large enough to make 

 this trend very apparent. 



The next day, plotting of the slab to be taken out was begun. 

 Because of the weight of the material, it was decided to take the piece 

 out in three sections. Accordingly chalk lines were laid out and 

 the work of quarrying started. This was carefully done, as the speci- 

 mens lying in the path between the slabs were fragile, and a successful 

 attempt was made to quarry these as well. 



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