The American Geologist, Voi,. XXVIII. 
Pt.atk tit 
Fig. 4. — Concave parting in Medina sandstone. Squire's quarry, Hulberton, N. Y. 
Lookinjj S. E. 
Fig. 5. — Crested ridge in Medina sandstone. McCorinick's quarry, Medinn, N. Y. 
Looking S. 1")° E. (The sharp line of the ridge crest is not properly shown.) 
Fig. 6. — Concavity in Medina sandstone. Whitmore quarrv. Lockport, N. Y. 
Looking N. 20° E. 
"Beach Stkuctukes in Medina Sandstone." — H. L. Faikciiild. 
