Skulls are fragile and rare in the quarry, because in every one of these big skeletons there were no fewer than ninety distinct bones which exceeded the head in size, the excess in most cases being enormous.
[Illustration: Fig.

45 .-- COLLECTING DINOSAURS AT BONE-CABIN QUARRY.
a.

The overlying soil and rocks are loosened with a pick and removed with team and scraper down to the fossil layer.
b.

The fossil layer is carefully prospected with small tools, chisels, awls and whisk brooms exposing the bones as they lie in the rocks.
c.

The blocks containing the fossils are channelled around, plastered over top and sides, undercut and carefully turned over and the under side trimmed and plastered.
d.