A Sea Tail

When Lorenzo, the Venetian boat captain, brought Dr. Manques to the isolated pier just down the canal from the Rialto Bridge, the last thing on the American's mind was a dead fish. Why would his friend need him to see this? It was a dead fish. Yes, Dr. Manques had his own sailboat. Yes, he knew the waters. But must he really kneel down and feel the scales. Scales were scales. Nevertheless, he would do as his friend asked. He knelt down and he felt the fish. Scale, scale, scale, scale, skin. What? He felt again. Scale, scale, scale, scale, skin. And his quasi-retired life as a recluse was now in serious jeopardy. What fish had scale and skin? Or alternatively what marine mammal had skin and scale? Nothing came to mind, except the possibility of a mythical species. Could it be? Could it really be? He was a man of science. He had been a dentist back in Oregon. This was inconceivable. A mermaid? No, no, no! But what else could explain it?