208 SYSTEMATIC PALEONTOLOGY 



This large globular cystid, as noted above, is so abundant in a lower 

 division of the Chambersburg limestone that it has received the name of 

 the Echinospherites bed. The reappearance of the species in the Chris- 

 tiania bed was noted only in southern Pennsylvania where a few speci- 

 mens were found at the higher horizon. 



Occurrence. CHAMBERSBURG LIMESTONE (Echinospherites bed). 

 Appalachian Valley of Pennsylvania, Maryland, West Virginia, and 

 Virginia. In Maryland specimens have been found at Pinesburg Station 

 and northward along the line of outcrop through Wilson to the state 

 line. The same form reappears, although rarely, in the Christiahia bed 

 of the Chambersburg limestone in southern Pennsylvania. 



Collections. Maryland Geological Survey, U. S. National Museum. 



Genus CARYOCYSTITES Von Buch 



CAEYOCYSTITES sp. 

 Plate XLI, Fig. 7 



Description. The strata of the Chambersburg limestone underlying 

 the Lowville division contain plates of a species of the cystid genus 

 Caryocystites so abundantly that the name Caryocystites bed has been 

 applied to them. The calyx of this cystid has not yet been found, but the 

 plates are easily recognized by the elevated, prominent pore rhombs on 

 their external surface. When weathered the plates also show the pores 

 or canals connecting with the pore rhombs and passing vertically through 

 the plate. 



Occurrence. CHAMBERSBUEG LIMESTONE (Caryocystites bed). Fort 

 Loudon and south to Blue Spring, Franklin County, Pennsylvania. 



Collections. Maryland Geological Survey, U. S. National Museum. 



