, 
AS ) = 
Ov of 
Nis 
NOE, DOI: NO. 7 
WASHINGTON 
JULY, 1911 
REPTILES 
OF ALL LANDS 
By Raymonp L. DiTmMars 
Curator oF ReEptites, N. Y. ZooL,ocica, PARK, AND AUTHOR oF “THE REPTILE 
Book,” “REPTILES OF THE WORLD,” ETC. 
shielded forms that make up the 
class of reptiles, we have a vivid 
illustration of a rapidly degenerating 
race of creatures. ‘The reptiles of for- 
mer periods—of hundreds of thousands 
of years ago—were by far the most 
gigantic inhabitants of this globe. 
In comparison with the ages of other 
groups of the earth’s varied vertebrate 
life, the reptiles have passed. through 
some abruptly terminated epochs. Pale- 
ontology teaches us that the age of gi- 
gantic reptiles came to a sudden close. 
Important climatic changes or disturb- 
ances were probably responsible for this, 
for warmth is one of the absolute neces- 
sities of a reptile’s life. The earth is 
undoubtedly a far cooler sphere than 
during the age of the great reptiles. 
In consequence we find the legions of 
modern reptiles, the members greatly 
reduced in size, occurring compactly 
around the world within the equatorial 
parallels. As we look to the north or 
the south, away from the region of 
greatest heat, the number of species and 
the size of their representatives will be 
seen to rapidly decline. The reptiles of 
the temperate zones are of comparatively 
insignificant size and pass the cold season 
in an absolutely dorraanti hel het 
condition. 
|: THE, four perder of scaled and 
iy 
. NOV 9 1981 
LIBRARIES 
While the trend of evolution has been 
to greatly reduce the size of the surviv- 
ing reptiles, the variability and number 
of forms have as substantially increased. 
In the ages that are gone a bird's-eye 
view of the earth’s surface would have 
revealed varied, monstrous forms ium- 
bering here and there, reveling in an 
atmosphere reeking with humidity ; some 
browsing in giraffe-like fashion among 
high branches, others churning through 
the ‘sea in pursuit of their prey; even in 
the murky atmosphere itself cold-blooded 
creatures like gigantic bats flapped their 
way in pursuit of equally gigantic in- 
sects. 
While but a very few examples of the 
modern reptiles anywhere approach the 
size of their rock-bound and now fossil 
ancestors, they occur to the number of 
over 4,000 species. It should have been 
explained that a fifth order of reptiles 
has its place in classification. It is made 
up of a single genus and species, the 
tuatera, a lizard-like creature of New 
Zealand. It is the oldest surviving type 
of reptile and apparently related to the 
long-extinct ‘Plesiosaurus. 
CROCODILES AND ALLIGATORS 
Of direct, ancient lineage, the modern 
crocodiles and alligators furnish us with 
a hint of the gigantic forms of reptile life 
