Figure 179.—Adz, Type II, subtype a, with posterior median ridge (c. 788):

a, front, well ground narrowing towards poll, shallow chipping depressions not entirely removed; front edges distinct but irregular; greater outward slope of sides shows up more of coarsely chipped sides; b, back; coarse chipping from sides, distinct median ridge; triangular bevel with base angles cut off by grinding lower end of sides, bevel grinding on right passes back on to posterior surface, chin distinct; c, side; coarsely chipped surface bounded on right by front edge and on left by irregular back edge which divides it from back surface; front longitudinal convexity well marked; d, sections: three upper sections show up posterior median ridge giving sections a pentagonal appearance, also shows greater outward slope of sides; section through bevel shows convex curve of sides due to grinding lower ends towards cutting edge.