Meg alonyx in Holmes county, Ohio. — Clay pole. 127 
attempts to crush it. In this wa} r it has been known to strangle a 
dog while still held at arm's length. 
Such are the sloths of the existing world. But those of the 
past — their ancestors — were animals of immense size and massive 
build. They combined in their structure several points not found 
in any single animal of the order at the present day — a usual 
fact in palaeontology where the ancestor is less specialized than 
the descendant. 
IV. Fossils of this order. 
With a single exception all the extinct fossil sloths belong to 
the family of megatherians, and as might be expected they are 
found for the most part in South America, where the almost 
boundless pampas probably conceal countless multitudes of these 
monsters. For 000 miles what is now a waving sea of grass only 
a few feet above high-water level was one vast estuary of the 
rivers Parana and Urugua}- wherein their carcasses were buried. 
In his "Journal of a Naturalist," Charles Darwin says : 
"The number of the remains of these quadrupeds embedded in 
the vast deposits which form the pampas and cover the granitic 
rocks of Banda Oriental must be extraordinarily great. I believe 
a straight line drawn in any direction through the country would 
strike one of these skeletons or bones. They did not perish in the 
marshes or muddy river-beds of the present land, but their bones 
have been exposed by the streams cutting the deposits in which 
they were embedded. The whole area of the pampas is one wide 
sepulchre of these gigantic quadrupeds." 
Of the huge extinct sloths, of which Mr. Darwin here writes, 
the megatherium was the earliest discovered, and is also the largest. 
In 1780, on the banks of the Luxan, about three miles from 
Buenos Ayres, and 100 feet below the surface, an almost entire 
specimen was dug up, and, of course, sent to Spain, where it was 
set up in the Royal Museum at Madrid. This is the original of 
the figure current in nearly all works on natural history. It was 
described by the great French naturalist, Cuvier — the founder of 
vertebrate palaeontology — and by him named megatherium Ameri- 
