It would not be surprising to find that such a creature was descended from a remarkable ancestry; and, following it up, we are led far into the early history of the later geological times, when all life seems to have attained its maximum growth; in fact, it was an era of giants. The map-maker of to-day would be astonished if confronted with the coast-line of that early time. The coast-country from Nova Scotia to Yucatan was all under water, and what are now our plains and prairies was a vast sea, that commenced where Texas now is and extended far to the northwest. Even now the old coast-line can be traced. We follow it along from Arkansas to near Fort Riley, on the Kansas River, then, extending eastward, it traverses Minnesota, extending into the British possessions to the head of Lake Superior, while its western shores are lost under the waters of the Pacific Ocean. Such was this great Cretaceous sea, in whose waters, with hundreds of other strange creatures, lived the ancestor of our leather tortoise. The ancient sea, however, disappeared; the land rose and surrounded it; the great forms died and became buried in the sediment, and finally the water all evaporated, leaving the bottom high and dry,--an ancient grave-yard, that can be visited on horseback or by the cars. What is now known as the State of Kansas is one of the most favored spots, and here, embedded in the earth, have been found the remains of these huge forms. The bones were first seen projecting from a bluff, and, gradually worked out, proved to be those of a gigantic turtle that must have measured across its back from flipper to flipper fifteen feet, while its entire length must have been twenty feet or more. The name of this giant is the _Protostega gigas_, a fitting forefather for the great leather turtle of to-day. In some parts of the West the hardened shells of other and smaller turtles are scattered about in great confusion. Nearly all have been turned to stone, and, thus preserved, form a monument of this past time.