According to a report in the Rochester Herald, on July 14,1899, around 7 p.m. the lake was calm as the side-wheeler steamship, the Otetiani, was cruising down Seneca Lake. The passengers were enjoying themselves when they saw a large object in the water. The captain observed it with his telescope and gave the engine room orders to slow down. The Otetiani steered within 100 yards of what appeared to be the keel of a capsized boat. The crew prepared to lower a boat when the object quickly moved away.

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Captain Herendeen ordered full speed ahead and came alongside the thing when it raised its head, opened its mouth, and displayed two rows of pointed white teeth. One of the passengers was a geologist who thought the creature was an extinct North American marine lizard belonging to a group of fish-eaters. He described it this way: “Its head was perhaps four feet long and triangular in shape. Its mouth was very long and armed with two rows of triangular white teeth, as sharp as those of a shark, but in shape more like those of a sperm whale. The body was covered with a horny substance that was as much like the carapace of a terrapin as anything I know. The horny substance was brown in color and of a greenish tinge. The belly of the creature was cream white. Its eyes were round like those of a fish and it did not wink.