The "'Grypoceratidae "', predominant stock, established by Hyatt in 1900, are characterized by generally smooth, compressed, evolute to involute shells with the venter flattened to subangular Ornamenation is not common, but some forms bear nodes or keels.
12.
"Oxygonioceras ", named by Foeste, 1925, has a loosely coiled, dextrally torticonic shell with a rounded dorsum on the inside of the spiral and an angular or subangular venter on the outside; suture with broad lateral lobes and ventral siphuncle with expanded, nummuloidal segments.
13.
BC 42 to; red ( 2.5YR 4 / 8 ) clay loam; few distinct yellowish red ( 5YR 5 / 8 ) mottles; weak medium subangular blocky structure; friable; few fine flakes of mica; very strongly acid; gradual wavy boundary . ( 0 to thick)
14.
Bt2 26 to; red ( 10R 4 / 8 ) clay; few fine prominent yellowish red ( 5YR 5 / 8 ) mottles; moderate medium subangular blocky structure; firm; sticky, plastic; common clay films on faces of peds; few fine flakes of mica; very strongly acid; gradual wavy boundary . ( Combined thickness of the Bt horizon is 24 to 50 inches)
