"But it was different out upon the rose-tinted waters of the central lake. It boiled and heaved with strange life. Great slate-colored backs and high serrated dorsal fins shot up with a fringe of silver, and then rolled down into the depths again. The sand-banks far out were spotted with uncouth crawling forms, huge turtles, strange saurians, and one great flat creature like a writhing, palpitating mat of black greasy leather, which flopped its way slowly to the lake. Here and there high serpent heads projected out of the water, cutting swiftly through it with a little collar of foam in front, and a long swirling wake behind, rising and falling in graceful, swan-like undulations as they went. It was not until one of these creatures wriggled on to a sand-bank within a few hundred yards of us, and exposed a barrel-shaped body and huge flippers behind the long serpent neck, that Challenger, and Summerlee, who had joined us, broke out into their duet of wonder and admiration."Plesiosaurus! A fresh-water plesiosaurus!" cried Summerlee. "That I should have lived to see such a sight! We are blessed, my dear Challenger, above all zoologists since the world began!""