TORTOISES. 67 



which are allied to this Cistudo ; and similar forms occur also 

 in Carolina arid Tennessee. 



The most abundant tortoise of the Swiss Miocene is* the Tes- 

 tudo Escheri, Pick, which was spread all over Switzerland at 

 the period of the upper freshwater Miocene formation. It has 

 been found at Locle, Veltheim, Elgg, and the Steinerberg, and 

 is most nearly related to the Greek tortoise (T. graca, Linn.), 

 which occurs in the Mediterranean countries, and is often 

 carried about for exhibition by Savoyard boys. From this it 

 differs in the form and size of the bones of the plastron ; its 

 length is '22 metre (or 8*661 inches), and its breadth -16 metre 

 (or 6*3 inches) . With it, at Veltheim near Winterthur, two other 

 species of much larger size have been discovered ; in one of 

 these (T. vitodurana } Biederm.) the carapace is nearly 1 metre 

 (or 3 feet 3'371 inches) in length and * 76 metre (or 2 feet 

 5 -92 inches) broad ; in the other (T. Picteti, Biedem.) it is 

 78 metre (or 2 feet 6*709 inches) long, and *52 metre (or 

 1 foot 8*472 inches) broad. These species, therefore, rival in 

 size the gigantic Indian tortoises. 



The alligator-tortoise of (Eningen ( ChelydraMurchisoni, Bell) , 

 of which beautiful specimens have been found, was also of con- 

 siderable size. The length of the carapace is '43 metre (or 1 foot 

 4*929 inches), with a breadth of '38 metre (or 1 foot 2*961 inches) 

 and the whole length from the tip of the snout to the end of the 

 tail was nearly a metre (or 3 feet 3*371 inches). It has pre- 

 cisely the same oval carapace, with its two extremities obtusely 

 rounded, the small cuneiform plastron, the five-clawed fore feet, 

 and the long tail which characterize the American species. As 

 no similar tortoises occur in the Old World, this is one of the 

 most striking American forms of the Swiss Miocene land; it is 

 probably to be regarded as the ancestor of the American species, 

 and no doubt had the same mode of life as the latter, which is 

 described as a rapacious and voracious animal, living upon fishes, 

 amphibia, and young birds. It darts, with its long neck erected, 

 upon its prey, which it seizes with its powerful jaws and large 

 claws. It inhabits rivers and lakes of the United States, from 

 New York to Florida, and especially belongs to warm and southern 

 regions. 



The river-tortoises (Emys) of the Miocene of Switzerland are 

 smaller animals. They have a broad immovable plastron, and a 



