GIANT SALAMANDERS 
135 
water animals, as we shall learn later on. A second species 
(Chelydra rossignonii) is confined to Mexico and Guatemala. 
The so-called alligator snapping-turtle (Macroclemmys tem- 
minckii), which belongs to another genus, frequents the 
rivers emptying into the Gulf of Mexico, being common in the 
Mississippi as far north as Missouri. Now the most striking 
zoogeographical feature of the family Chelydridae is, that 
right across the Pacific Ocean we meet with another snapping 
turtle (Devisia mythodes) in the Fly River of New Guinea, 
the same river that contains the unique members of the family 
Carettochelyidae. In many other respects New Guinea has 
acquired the reputation of being the home of remarkable and 
peculiar types of animals, and no doubt the island .once 
formed part of an ancient land, most of which has long since 
been submerged. 
Quite as instructive and important from a distributional 
point of view as the reptiles are the amphibians. We can 
roughly divide the latter into tailed amphibians, such as the 
newt and salamander, and tailless ones, of which the frog 
and toad are examples. All these are amply represented in 
the north-eastern States of North America, and we notice 
among them that same curious relationship between eastern 
America and eastern Asia which has given rise to so much 
comment among naturalists. 
Two kinds of giant salamanders are known to exist in the 
world. One of these, the so-called “hellbender” (Crypto- 
branchus allegheniensis), lives in the eastern States of North 
America, the other, (Cryptobranchus or Megalobatrachus 
japonicus), in the mountain streams of Japan. The hell¬ 
bender is a voracious lead-coloured slimy creature, living 
in the Allegheny and other eastern rivers, where it feeds on 
worms and fish. It grows to a length of two feet, while 
its Asiatic relative attains to double that size. Of the geo¬ 
logical history of the giant salamanders we know nothing 
as far as America and Asia are concerned, but in the Miocene 
of Switzerland a large amphibian was discovered, which 
appears to be closely allied, though now referred to the 
distinct genus Proteocordylus. To suppose that these relicts 
of bygone ages are no older than Miocene would scarcely be 
justified. In the absence of palaeontological evidence, w r e must 
