146 PHYSIOGRAPHY AND GEOLOGY OF THE COASTAL PLAIN PROVINCE. 



In the old cut just above the shell bed the sand is filled with casts of 

 Chama while the upper part of the shell bed is quite firmly indurated in 

 places and some of the shells are filled with calcite crystals. The shell bed 

 here contains besides the fossils already named, PJiacoides, Ostrea, FissvreJ- 

 la, and Venus. 



The Pleistocene in the old cut contains near its base in one place a 

 ledge of iron sandstone about 10 inches in thickness. The railroad track is 

 about 25 feet above the river. There is no good exposure but it seems that 

 everything from railroad track to the water consists of loose buff sand. 



II. Section right haul- of Yorl- River at Mount Folly. 



Feet 

 Pleistocene Bi'own and mottled loam becoming sandy to- 

 ward base 15 



Brown sand in places indurated by iron to form 

 quite firm sandstone 10 feet thick 15 



Miocene. St. IMary's Buff sand containing considerable drab clay. . 15 



Buff sand containing grains of magnetite .... 25 

 Shell layer containing numerous specimens of 

 Melina maxillata, Pecten jeffersonius, var. 

 sepfenariiis : Ostreo compressirostra ; some- 

 what indurated 2 



Light-colored buff sand 10 



Greenish-blue fine sand 2 



Total 84 



SECTIONS IN THE JAMES RIVER VALLEY. 



The St. Mary's formation is well exposed in several places in the James 

 Eiver bluffs where the fossiliferous strata liave long been known as excellent 

 collectina: grounds. 



I. Section rigtit bank of James River, one and one-quarter miles above, 

 Chiremoiit Wharf (JKst belotr Old Clarvinoiii Wharf). 



Feet 

 Pleistocene Yellow sand with some loam at top and 



pebble bund at base IG 



Miocene. St. jMary"s Sliell bed, shells in matrix of yellow sand, 



forms varied and well preserved 12 



Yellow sand without fossils 15 



Shell layer, shells in matrix of blue sand.. 10 

 P.hie sand grading into ov«rlying stratum 

 containing numerous specimens of Turritel- 

 la. Exposed to water 6 



Total 59 



