104 ANIMALS OF THE PAST 
this weight of skull and body requires very | 
massive legs, and as the fore legs are very _ 
short, this enables Triceratops to browse com- 
fortably from the ground by merely lowering 
the front of the head. 
‘These forms we have been considering were 
the giants of the group, but a commoner spe- — 
cies, Thespesius, though less in bulk than those 
just mentioned, was still of goodly proportions, ~ 
for, as he stalked about, the top of his head ~ 
was twelve feet from the ground. | 
Thespesius and his kin seem to have been 
comparatively abundant, for they have a wide © 
distribution, and many specimens, some almost ~ 
perfect, have been discovered in this country — 
and abroad. No less than twenty-nine Igu-— 
anodons, a European relative of ‘Thespesius, . 
were found in one spot in mining for coal at 
Bernissart, Belgium. Here, during long years ! 
of Cretaceous time, a river slowly cut its way 
through the coal-bearing strata to a depth of 
750 feet, a depth almost twice as great as — 
the deepest part of the gorge of Niagara, 
and then, this being accomplished, began the — 
work of filling up the valley it had excavated. — 
