728 SIMO DIGES SHON SIMGMOIBIN IES 
Apholidomys and Pseudotrionyx are from the Eocene of France. 
The true land turtles, Zestudo, mostly, are characterized by the 
great elevation of the carapace and the smoothness of its bones. 
The claws of the toes are in many cases shortened till they 
appear as broad nails. The earliest forms known are from the 
Eocene of Wyoming and New Mexico, the Wasatch and Bridger. 
In Europe the earliest forms occur in the Oligocene. Through- 
out the Miocene and the Pliocene layers of both the old and the 
new world, the genus abounds. The best region for the remains, 
however, is the Bad Lands of South Dakota, Miocene or Oligo- 
cene, where they occur in great abundance. 
Especially remarkable was the gigantic Collosochelys of the 
Siwalik Hills of India (fresh-water Miocene). The animal was 
fully 18-20 feet long, the carapace alone being 12 feet long and 
8 feet high. 
From the Pleistocene of Queensland, Australia, comes the 
peculiar form Mezolania, which possessed horns or bony protuber- 
ances on the skull. 
During Pleistocene times many of the islands of the East 
Indies were inhabited by enormous land turtles. Remains of 
such are known from Mauritius and Rodrigues. Similar remains 
are known from the Island of Malta and on the Galapagos 
Islands off the coast of Central America there are still living 
forms of the same group. 
The Pleurodira are the forms in which the bones of the pelvis 
are joined by sutural union to the bones of the carapace and 
plastron above and below. They are few in number in recent 
times, and were little if any more numerous in past time, though, 
peculiarly enough, the most ancient turtle known is a member 
of this suborder. Proganochelys, from the Upper Triassic ( Keupfer- 
sandstein) of Germany, Plestochelys, from the Upper Jurassic of 
England, and Bothremys, of the New Jersey Cretaceous, are also 
members of the same group. 
PROGANOSAURIA. 
These forms are of the greatest interest from a phylogenetic 
standpoint. They are generally regarded as the most primitive 
