290 THE ANTIQUITY OF MAN 
represented in his first discovery. There is no question, 
then, that Dr Ameghino's first discovery represented a 
burial. It is clearly not a burial made from the present 
land surface, but when and how it was made are problems 
which cannot now be solved definitely. The human 
remains are clearly of some degree of antiquity. 
In 1902, at the age of forty-eight and after an uphill 
life-struggle, Ameghino found himself Director of the 
Nationat "Museum of Buenos Aires. With a series of 
discoveries, following each other in rapid succession, he 
really startled the anthropologists of Europe. He claimed 
to have discovered fossil forms which demonstrated the 
evolution of modern man — or of a form of man of the 
modern type — in the southern regions of South America. 
The oldest and most primitive human ancestor he named 
Tetraprothomo, and regarded the only remains which 
were found of this ancient, human type — an atlas and a 
thigh bone — as of Miocene age. As will be seen from 
fig. 94, the remains of Tetraprothomo were discovered 
at Monte Hermosa, on the east coast of Argentina, some 
distance north of the mouth of the Rio Colorado. 
The second and later stage in man's evolution — 
Diprothomo — was based on the fragment of a skull, 
obtained from a formation which he regarded as of early 
Pliocene date. The third link in Ameghino's human, 
ancestral chain was Homo pamp^us^ also a Pliocene form. 
The fourth and final stage, Homo sapiens^ appeared in the 
Pleistocene deposits of the pampas.^ 
It will be sufficient to give a brief account of the 
discovery of Ameghino's early Pliocene forerunner of 
man — Diprothomo. In 1896 an English firm of con- 
tractors had almost finished the construction of a dry 
dock on the south bank of the La Plata, at Buenos Aires. 
The concrete floor of the dock had been sunk to a depth 
of 12-36 m. (407 feet) below the level of the water at 
low tide. Subsequently, an additional hollow, 20 inches 
deep, had to be sunk through the floor of the dry dock, 
reaching a total depth of about 42 feet below the level of 
1 For full account, see references on p. 288. 
