382 The Upper Devonian Deposits of Maryland 



■with tlicse blocks are others containing clay pebbles as well as those 

 of quartz that do not break with a smooth fracture. Possibly both kinds 

 of blocks are from conglomerates occurring very near the top of the 

 Jennings formation. In conjunction with the conglomerate blocks are 

 numerous ones of reddish sandstone and it is thought that the Catskill 

 formation begins in the lower part of this ridge. On the northern side 

 of the road are numerous blocks of brownish-red sandstone and an 

 occasional brownish-gray block containing Chemung fossils, mostly pele- 

 cypods, but no blocks of conglomerate were noticed. 



Exposure on Salisbury Road. — On the Frostburg-Salisbury Eoad, which 

 leaves the National Eoad on the ridge northwest of Mr. Johnson's is red 

 Catskill soil continuing to the base of the first northwestern slope. At this 

 point there are loose blocks of conglomerate which do not break smoothly 

 across the pebbles and probably come from a thin conglomerate stratum 

 at about the top of the Jennings. On the second slope are loose, some- 

 what porous, conglomerate blocks of a rather brownish-gray color bearing 

 no resemblance to the conspicuous flat pebble conglomerate. At this 

 point are brownish-red sandstones and greenish shales and sandstones in 

 some of which are Chemung fossils, as Productella and a few other 

 brachiopods. 



In the second hollow, however, and in the fields, opposite the house of 

 Philip Baker, are numerous loose blocks of the flat pebble, jasper con- 

 glomerate. This locality is about 11/4 miles northwest of Mr. Johnson's, 

 51:4 miles from Frostburg and 1 mile south of the Pennsylvania line. 

 One of the blocks measured 10 inches which shows that it came from a 

 stratum of considerable thickness. There are numerous pebbles of white 

 quartz of fair size, an occasional one from 1 to 1% inches across, some of 

 rose quartz and a number of jasper. In the lines of jointing these flat, 

 lenticular pebbles are broken with an even fracture making a perfectly 

 smooth surface of rock. The pebbles neither project nor by falling out 

 make pits, so that the plane of the break is as smooth as if the rock were 

 composed of amorphous material. The fracture is so smooth that it may 

 be said to be almost flinty. The matrix is grayish to brownish-gray but 

 much rust stained in many of the blocks from weathering. 



