7o6 - GEORGE W. STOSE 



quarried at Stoufferstown and Stonehenge east of Chambersburg. 

 In the Mercersburg quadrangle, chert is sufficiently plentiful in the 

 soil derived from the Beekmantown to produce low ridges. One 

 horizon is just above the siliceous banded limestone of the Stonehenge 

 member and in the Mercersburg area is included with the siliceous 

 phase. The cherts are of various forms. Some are large, rough, 

 scoriaceous masses, others are flinty in texture, banded, brecciated, 

 granular, and oolitic ; while the most unique forms are composed of 

 super-imposed rosettes resembHng heads of cauliflower. A Cryptozoan, 

 apparently of the species described by Winchell as C. minnesotensae, 

 occurs in these cherts. 



An upper horizon of cherts, many of the small rosette form, occurs 

 at the top of the Beekmantown in both areas, but is a ridge maker 

 in the Mercersburg quadrangle. 



The Beekmantown limestone is one of the most widely distributed 

 formations in the area, occurring in a broad belt across the western 

 half of the Chambersburg quadrangle, and in several anticHnal areas 

 in the Mercersburg quadrangle. Its outcrops are generally deeply 

 covered with soil with infrequent exposures, and furnish excellent 

 farm land. 



In the eastern belt it is closely folded in common with the enclosing 

 limestones, and its outcrop is consequently very irregular in outline 

 and width. In the Mercersburg quadrangle it forms large lens-shaped 

 areas in the anticlinal uplifts of Welsh Run-Edenville, Mercersburg, 

 Foltz, and McConnellsburg. 



Although its fauna has been previously observed at various places 

 in the Appalachian Valley, the Beekmantown has not heretofore been 

 recognized as a distinct formation in this region, and little is known 

 of its extent beyond the immediate vicinity of the area. It is known 

 to maintain its lithologic and faunal characters as far northeast as 

 Mechanicsburg, Pa. Although sparingly fossiliferous as a whole, 

 a rather large variety of forms have been collected in this 

 area. 



The lower portion of the formation, including the Stonehenge 

 member, is characterized by Ophileta complanata and of the 13 

 species collected the following have been identified by Mr, 

 Ulrich: 



