Hiatella rugosa. Periostracum covers siphons, and much survives on valves; difficult to explain if boring action into solid limestone is by mechanical movement of valves unaided by chemical or muscular action of foot.
Hiatella rugosa. Periostracum covers siphons, and much survives on valves; difficult to explain if boring action into solid limestone is by mechanical movement of valves unaided by chemical or muscular action of foot.
Hiatella rugosa. Periostracum covers siphons, and much survives on valves; difficult to explain if boring action into solid limestone is by mechanical movement of valves unaided by chemical or muscular action of foot.
